GCSE Information Technology
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GCSE Information Technology
Contents
Chapter 0 - Introduction
0.1 About this book
0.2 Applications Used
0.3 Questions/Answers
0.4 Optional Research
0.5 Bookmarks
Chapter 1 - Introduction to Information Technology
1.1 Definitions for this Chapter
1.2 Information Technology - Defined
1.3 Digital vs. Analogue
Chapter 2 - Information and Data
2.1 Definitions for this Chapter
2.2 Information and Data
2.3 Data Types
2.4 Character Sets
2.5 Coding Data
2.6 Processing Information
Chapter 3 - Computers and Types of Processing
3.1 Definitions for this Chapter
3.2 What makes up a Computer?
3.3 Types of Computer
3.4 Types of Processing
Chapter 4 - Capturing and Inputting Data
4.1 Definitions for this Chapter
4.2 Data Capture
4.3 Inputting Data
Chapter 5 - User Interfaces
5.1 Definitions for this Chapter
5.2 User Interfaces
Chapter 6 - Outputting Data
6.1 Definitions for this Chapter
6.2 What is an output device?
6.3 Monitors
6.4 Printers
6.5 Other Output Methods
Chapter 7 - Storing Data
7.1 Definitions for this Chapter
7.2 Storage
7.3 How a disc works
7.4 Accessing Storage
7.5 Files
7.6 Security of files
Chapter 8 - Applications Software
8.1 Definitions for this Chapter
8.2 Software, Programs and Applications Software
8.3 Types of Application Package
8.4 Deciding which package to buy
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GCSE Information Technology
Contents
8.5 Some typical packages
8.6 Communication between packages
Chapter 9 -Word Processing
9.1 Definitions for this Chapter
9.2 Introduction to Word Processing
9.3 Margins
9.4 Indents
9.5 Tabs
9.6 Blocks of text
Chapter 10 - Databases
10.1 Definitions for this Chapter
10.2 What is a database?
10.3 Setting up a database
10.4 Using a database
Chapter 11 - Spreadsheets
11.1 Definitions for this Chapter
11.2 Models
11.3 Spreadsheets
Chapter 12 - Graphics
12.1 Definitions for this Chapter
12.2 Graphics
Chapter 13 - Communications and Networks
13.1 Definitions for this Chapter
13.1 Introduction to Communications and Networks
13.3 Types of Network
Chapter 14 - Control Systems
14.1 Definitions for this Chapter
14.2 What is a Control System?
14.3 Communicating with the devices
14.4 What can the computer control?
14.5 Feedback
14.6 Turtles and LOGO
Chapter 15 - Developing Systems
15.1 Definitions for this Chapter
15.2 The System Life Cycle
Chapter 16 - Documentation
16.1 Definitions for this Chapter
16.2 Types of documentation
16.3 Flowcharts
Chapter 17 - The impact of IT
17.1 Definitions for this Chapter
17.2 A brief History
17.3 The effect IT have had on our lives
Chapter 18 - Your Coursework Project
18.1 Introduction
18.2 What shall I do for my coursework?
18.3 How do I do my coursework?
Chapter 99 - Answers to Questions
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GCSE Information Technology
Chapter 0 - Introduction
Chapter 0 - Introduction
0.1 About this book
This book is for Information Technology GCSE Key Stage 4. It is known as a short
course. This means, in order to get a GCSE certificate the students have to continue
with their IT studies to convert the course into a GCSE for Information Systems.
Alternatively, they can combine Information Technology with another subject to give
a combined GCSE.
This book covers the syllabuses for all examination boards.
0.2 Applications Used
This book was written using Microsoft Office (Word 6, Excel 5 and Access 2). The
screen shots are taken from these packages.
However, the book does not assume the student is using any particular package.
The author would like to thank Microsoft for permission to use the screen shots.
0.3 Questions/Answers
Most sections have questions at the end. These check the students understanding of
the material just presented. The teacher can obviously choose which questions to use
and can incorporate their own.
Suggested answers to the questions are given in Chapter 99. For obvious reasons, the
students should not be given access to this chapter.
0.4 Optional Research
At the end of each chapter there is normally an ‘optional research’ section. This
material is not examinable but could be used as exercises for students who show a
strong interest in IT.
0.5 Bookmarks
In order to make this book as easy to use as possible ‘bookmarks’ have been placed at
the start of each chapter. If you use Word to read this book you can use the
Edit/Bookmark menu to display a dialogue box; like this:
You can now select the Chapter you want to go to and Click on Go To.
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GCSE Information Technology
Chapter 1 - Introduction to Information Technology
Chapter 1 - Introduction to Information Technology
1.1 Definitions for this Chapter
Information Technology (IT) : Describes the equipment and software used to process
information. It is not only used when talking about computers.
Digital : Describes something which can be in a known numbers of states.
Analogue : Describes something which is continuously variable - for example sound
or
the level of a river.
1.2 Information Technology - Defined
The term Information Technology (IT) is used to describe the equipment we use to
process information and the software we use to carry out those processes.
A calculator is an example of IT. It is a piece of technology that processes numbers
that we enter into it.
A telephone is another example. It processes the sounds that we make so that they can
be understood by somebody, perhaps, on the other side of the world.
Of course, a computer is another (and perhaps the most common) example of IT. It is
also probably the most versatile example of IT as it can be used as a Word Processor,
a Database, a Spreadsheet; in fact a computers uses are also unlimited.
There are generally considered to be five main areas of IT; these being:
1. Handling Information : This includes sorting data, searching for data and carrying
out analysis on data. This is typically done by a database program but many other
types of program also carry out these operations.
2. Communicating Data : Using IT it is possible to send data around the world by
telephone lines, radio waves - even microwaves. Before this technology was
available it could be weeks or even months, before you could get access to
information on the other side of the world.
3. Measuring and Control : This area of IT allows a machine to interact with the
outside world and act on the input it receives. For example, a car production line is
able to sense when a car body is in a certain position and weld together the relevant
parts of the car.
4. Presenting Information : IT is useless unless the output of the various processes
is presented in a form we understand. Word Processors, Desk Top Publishers even the television - takes raw data and presents it in a format we can understand
and find attractive.
5. Modelling the Real World : Using simulations we can see what happens if we do
something without having to do it for real. The government, for example, may run
a simulation to see what would happen if they were to raise interest rates.
Spreadsheet applications are often used to build models of, say, a company’s
accounts.
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Chapter 1 - Introduction to Information Technology
Q.1.2 Questions
Q.1.2.1 Give three examples of IT, that you use every day.
Q.1.2.2 Looking at the five main areas of IT, above, give one example of each area
that you use in everyday life
1.3 Digital vs. Analogue
In IT you will often hear the term digital and occasionally the term analogue. But what
do they mean?
Digital : If something can be in one or more specific states it is said to be digital. For
example, a light switch is either on or off - it cannot be in between. This could be
described as a digital device. Another example are the coins in your pocket. They
can only take certain values. A single coin cannot represent a value of, say, seven
pence.
Analogue : If something varies continuously it is said to be an analogue device. For
example, a river is analogue as its level is constantly changing. Another example is
a television signal. The picture is represented by a constantly varying signal which
eventually arrives at your TV set.
Q.1.3 Questions
Q.1.3.1 Would you consider the following digital or analogue?
i The music coming from a speaker
ii The price of postage stamps
iii Whether a bank account is in credit or debit (in the black or in the red)?
iv The different combinations of colours a traffic light can have
Q.1.3.2 Give an example of something which is digital and something which is
analogue?
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Chapter 2 - Information and data
Chapter 2 - Information and Data
2.1 Definitions for this Chapter
Information : Facts and knowledge that has meaning.
Data : Information that is held in a form that can be processed.
Data Type : Describes how a piece of data can be used and stored.
Data Processing Cycle : The sequence of events that is used to process information.
2.2 Information and Data
Information and data are fundamental to IT. Everything we consider in this book is
somehow related to Information and Data.
But what is the difference between the two terms? As can be seen in the definitions
(above), information has some sort of meaning whereas data is information in a form
in which it can be processed.
Here are some examples:
Information




A telephone directory.
A company report.
A class register showing who has attended each day.
A letter produced on a word processor.
Data
 The names which are in a telephone directory.
 A company report stored in a word processor document.
 A list of students in a class.
Notice how the information has meaning. By comparison, the data does not have
meaning; at least not until we do something to convert it (process it).
For example, a company report stored on your computer does not have meaning. But
if we apply a process to it (in the form of a Word Processor) we can print something
that does have meaning.
Sometimes it is not always easy to decide if something is information or data.
A list of students in a class could be information if all you wanted to know was who
was in the class. But if you wanted to know who has attended each day the data would
need to be processed so that it is a class register.
In some cases data and information is different depending on who is looking at it.
If you cannot read French, a book written in that language is just data but it is
information to somebody who understands the language as they can make sense of the
words.
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Chapter 2 - Information and data
Q.2.2 Questions
Q.2.2.1 Give two examples of information?
Q.2.2.2 Give two examples of data?
Q.2.2.3 Whether something is information or data sometimes depends on who is
looking at it. Give two examples where this could be the case and say who would
regard it as information and who would regard it as data?
2.3 Data Types
A data type describes how data is processed and stored.
The number 3.67 is a numeric data type. Being numeric we can perform calculations
on it. We could, for example, add 34.78 to it.
The characters ‘computer’ is a string data type. It makes no sense to add 34.78 to the
word computer.
As well as dictating the operations that can be performed on the data, the data type
also defines how the data is stored. Numeric values are normally stored in a special
format that makes calculations easier for a computer to do.
2.3.1 Examples of Data Types
These are some of the common data types. There are others and, sometimes, you are
allowed to define your own.
Character
String
Numeric
Integer
A single letter, punctuation character or number. For example ‘a’, ‘!’
and ‘3’. There are also special characters which cannot be printed or
seen on the screen. If you are printing a report and the printer starts a
new page a ‘Form Feed’ control character has been sent to the printer.
Although you cannot see a ‘Form Feed’ on the screen it is still a
character.
There are also other characters which are simple graphics. Using these
you can get special effects such as drawing a border around a screen.
A series of characters. For example, “This is a string”. A string that
contains both letters and numbers is sometimes referred to as an
alphanumeric data type
A number. For example 12.45, -678.98, +5.89234
A whole number. For example 12, 19862, 100861
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Chapter 2 - Information and data
Q.2.3 Questions
Q.2.3.1 Look at the following data and say which data type best describes it
i
12
ii
a
iii
aa
iv
-34.98
v
A telephone number
vi
Your age
vii
Your Christian Name
2.4 Character Sets
A character set is a complete set of characters used for a specific purpose.
The character set for a computer typically consists of 256 characters (called the ASCII
(pronounced askey) character set). This contains all the characters that your computer
uses. It includes all the numbers, letters and punctuation symbols. It also includes
many other characters; some of which are not printable (for example a form feed
character).
Q.2.4 Questions
Q.2.4.1 What characters do you think make up the character set of the English
language?
Q.2.4.2 What is the character set for all the non-vowel characters in the English
alphabet.
2.5 Coding Data
You already use codes in your everyday life without even realising it. A date such as
21/07/61 is a code for 21st July 1961. A time given as 21:15 is a code for a quarter
past nine in the evening. Your bank account number is a code that represents your
account within the bank.
Computers also use codes to store data. Some of the reasons for this are as follows.
 It uses less space. An international company might use a two character code to
represent a country rather than the full name of the country; say ‘UK’ instead of
‘United Kingdom’.
 It makes the data easier to handle. In the above example manipulating “UK” is
easier (and faster) than having to manipulate “United Kingdom”
 It is more consistent. Users are less likely to make a mistake entering ‘UK’ rather
than ‘Unitex Kingdom’ (see what I mean?)
 The computer is able to perform validation easier as there are only a certain number
of codes. By contrast you might enter ‘United Kingdom’, ‘Britain’ or ‘England’ to
represent the same country.
Of course, there are problems with using codes. Probably the main one is the fact that
the user has to be familiar with the codes being used or else keep looking them up.
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Chapter 2 - Information and data
However this is not so much of a problem these days as the computer themselves can
assist in the process and make the codes being used almost invisible to the users.
Q.2.5 Questions
Q.2.5.1 Give three examples of where you use codes in your daily life, almost without
realising it.
Q.2.5.2 If you were asked to introduce a coding scheme for the Premier Division
Football teams how would you do it? As well as devising a coding scheme what else
would you need to think about?
2.6 Processing Information
Computers are all about processing information (normally called Information
Processing). There is a typical sequence of events in processing information called the
data processing cycle. The normal sequence of events is;
1. Data Collection is the collection of data from whichever source you are using. It
might be a survey conducted on the High Street, figures from company accounts or
the names of people who will be attending school next term.
2. Data Input is inputting the data into the computer. How and where you input the
data will depend on the type of data, the equipment you have available and the type
of software you are using.
As the data is input it is checked (validated) and stored on the computer in a
suitable format for later processing. The concept of a data type (covered above) is
important in the input phase of the data processing cycle.
3. Processing is converting the data from one form to another. Maybe, a set of
company accounts for a High Street retailer needs to be sorted into some sort of
order. Maybe you want to use the data you have inputted to produce summary
information by adding up all the figures for each store to give one total.
4. Output is concerned with producing output from the data in a form acceptable to
the person processing the data. Maybe the output will be a set of company accounts
ready to submit to the tax office. Maybe, for a supermarket, it will be bar code
labels that they will put on the shelves, together with a price for each item.
This cycle continues so that after you have produced the output you will go back to the
beginning and collect more input. For example, a supermarket will receive deliveries
and sell goods. This data has to be collected and input to the computer on a daily
basis.
Q.2.6 Questions
Q.2.6.1 Consider a class register. Identify what happens to it during the various phases
of the data processing life cycle.
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Chapter 2 - Information and data
R.2 Optional Further Research
R.2.1 The ASCII character set is the most commonly used character set. What does
ASCII stand for?
EBCIDIC is another common character set. What does EBCIDIC stand for?
Get a copy of the ASCII character set and find out how many control characters there
are.
R.2.2 What code is used to uniquely identify a book? What does each part of the code
represent?
R.2.3 A light switch could be described as a binary device. What is meant by binary
and why is it important with regards to computers?
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Chapter 3 - Computers and Types of Processing
Chapter 3 - Computers and Types of Processing
3.1 Definitions for this Chapter
Computer : A device that processes data that has had input put into it. The processing
is done via a series of fixed instructions, usually called a program.
Central Processing Unit : The main part of the computer which controls all the other
parts of the computer.
RAM : Random Access Memory. Temporary storage in a computer that holds
programs and data.
ROM : Read Only Memory. Similar to RAM but you cannot write to the memory.
Normally stores programs which never change.
Discs : Used for permanent storage of data. There are three types of disc; Hard Discs,
Floppy Discs and CD-ROM’s.
Hardware : The physical pieces of equipment that make up a computer.
Software : The instructions that tell the computer what to do.
Personal Computer (PC) : A computer used by one person at a time.
Mainframe Computer : Large computers that can look after many jobs and users at
the same time.
Minicomputer : A computer that is more powerful than a PC but not as powerful as a
mainframe. Usually runs many jobs and has many people attached to it at the same
time.
Stand-Alone system : A computer used by one person at a time.
Multi-User system : A computer used by many people at the same time.
Real Time Processing : A computer that reacts to input as soon as it receives it.
Interactive Processing : You communicate with the computer and it responds; like a
two way conversation.
3.2 What makes up a Computer?
Before we start to look at the things that computers can do it is useful to know what a
computer is and identify the various parts that make up a computer.
What we are about to discuss is a typical computer.
 Computers are built using Hardware and Software.
The best definition we have ever heard for Hardware is “If you kick it, it clangs.”
From this you might be able to work out that hardware are all the physical bits and
pieces like the screen, the keyboard, the mouse and the computer case.
Software is what makes it all work. Software are the instructions to the computer
that tell it what to do. Software is often referred to as programs or applications.
 Every computer has a Central Processing Unit (CPU). This is the main part of the
computer and it controls everything the computer does; including looking after
access to devices (such as printers) which are not part of the CPU.
 Memory is used by the computer to store data. There are three main types of
memory
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Chapter 3 - Computers and Types of Processing
 RAM (Random Access Memory - also called Read Write Memory). This
memory is used as a temporary storage area. It is temporary as the contents of
RAM is lost when the computer is switched off.
RAM is used to hold programs that the computer is currently processing and
also to hold data which the program is using.
 ROM (Read Only Memory). This type of memory is like RAM except it can
only be read; unlike RAM which can be read and written to. ROM is put into
the computer by the manufacturer and it typically contains programs that are
used by the system itself. For example, the program that recognises when you
press a key on the keyboard could be in ROM.
 Backing Store, which is normally in the form of a disc or a magnetic tape.
There are three types of disc; Hard disc, Floppy Disc and CD-ROM.
 Hard discs are situated inside the main case of the computer and are used
for day to day storage.
 Floppy discs can be put into the computer and then have data copied onto it;
either for security purposes or so the data can be transferred to another
computer.
 CD-ROM’s are read only and are usually used to distribute software.
Magnetic tape works in the same way as a cassette recorder except that it
records computer data rather than music or sounds.
All discs and tapes are persistent media in that they retain the information
on
them even if the power is switched off.
 Peripherals are anything that is outside the main case. For example a screen
or a printer.
Q.3.2 Questions
Q.3.2.1 If some data is in RAM why should you regularly copy the data to a disc
drive?
Q.3.2.2 What is one advantage of distributing software (programs) on CD-ROM as
opposed to using floppy discs?
Q.3.2.3 From the following list decide if each item is hardware or software?
i
A Floppy Disc
ii
A Word Processing Program
iii
A Computer Game
iv
A Joystick
3.3 Types of Computer
There are three main types of computer
3.3.1 Personal Computers
As the name suggests a Personal Computer (or PC) is for personal use. It is normally
used by one person (a single user system). In a school you will almost certainly be
using PC’s. The majority of people in large companies have PC’s on their desks.
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Chapter 3 - Computers and Types of Processing
3.3.2 Mainframe Computers
These are large computers that cost millions of pounds. They are used by large
companies and government departments such as the tax office. Mainframes have large
memories and storage capacities and often run 24 hours a day.
Mainframes are capable of looking after many jobs at the same time and have many
people using them at the same time. Many PC’s in companies are connected to the
mainframe.
Mainframes often hold all the information about the business and its customers which
is accessed by PC’s which are on the employees’ desks.
A mainframe is often in a secure area and has to be in an air-conditioned room due to
the amount of heat it generates.
Mainframe computers are known as multi-user systems as many people can use the
computer at the same time.
3.3.3 Minicomputers
Minicomputers come somewhere in between PC’s and mainframes. They are less
powerful than mainframes but are used when a PC is not powerful enough for the
required job.
Like mainframes, minicomputers often have PC’s attached to them so that the data
can be accessed from people’s desks.
Minicomputers are usually multi-user systems.
Q.3.3 Questions
Q.3.3.1 What do you think is a disadvantage of a multi-user system?
Q.3.3.2 What do you think is a disadvantage of a single-user system?
3.4 Types of Processing
Computers can do various types of processing. In this section we are going to consider
some of them.
3.4.1 Real Time Processing
If a computer is reacting to input as soon as it arrives and then producing some form
of output as soon as it has processed the data then it is known as a real time system;
that is, it’s processing the data in real time.
A bank cash machine is operating in real time. You are asking for money, your
account is checked and money is given to you providing you have sufficient funds.
An aeroplane is an even better example. If it is flying under automatic pilot it is
certainly operating in real time. If it gets too close to the ground it must do something
quickly. It is no good waiting ten minutes, finishing another job before it gets to the
input that says “the ground is fast approaching.”
Because real time processing requires the computer to always be able to process any
input, real time processing is normally done on a dedicated computer so that is does
not get side-tracked by other, less important, tasks.
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Chapter 3 - Computers and Types of Processing
3.4.1 Interactive Processing
If you sit at a computer and type an instruction and then receive a reply you are using
the computer in an interactive mode. If the computer is also being used by other
people, for example a mainframe computer at a bank, you may have to wait for the
computer to get around to processing your input and replying to you. But you will
receive a reply eventually.
If you are using a stand-alone computer (where you are the only person using it) the
reply could be almost immediate, unless you have asked the computer to carry out a
task that takes it a long time.
Most things you will be doing on a PC are examples of interactive processing. For
example, typing a letter using a Word Processor is an interactive task.
Q.3.4 Questions
Q.3.4.1 Do you think the following are interactive or real time processes, or both;
i A flight simulator
ii Using a calculator
iii Booking a holiday at a Travel Agents
iv A Crossword Puzzle on a computer
Q.3.4.2 When you buy a train ticket you can reserve a seat. Do you think the train
operator could use a single user system to provide this service? If not, why not?
R.3 Optional Further Research
R.3.1 There may be somebody at your school who will open up a computer case and
let you see inside. You may be able to identify the RAM, ROM and CPU. Do not
open the case yourself. It is dangerous and you may cause damage to yourself and
to the computer.
R.3.2 By using utilities on your computer you will be able to find out how much RAM
and disc space are installed on your computer. You can also find out how much data
can be stored on a CD-ROM.
R.3.3 Find out the name of a large company in your area that uses a large mainframe
computer. See if a visit can be arranged. Find out how the memory size and disc
capacity of their mainframe compares with a PC at your school.
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Chapter 4 - Capturing and Inputting Data
Chapter 4 - Capturing and Inputting Data
4.1 Definitions for this Chapter
Data Capture : Obtaining data that is then fed into a computer.
Bar Code : A series of black and white stripes which represent numbers and letters.
Magnetic Stripe : A strip of magnetically coated material. The strip contains
information which can be read by a reader.
Optical Mark Reading (OMR) : A system that read marks made on paper (typically
crosses or filling in boxes). The position of the marks represent the data.
Optical Character Recognition (OCR) : Converting marks on paper into characters,
for example, hand-writing.
Magnetic Ink Character Recognition (MICR) : Characters printed in a special way
with magnetic ink which can then be read by a special reader.
Digitising : Convert an image or sound from analogue to digital. The digital
representation can more easily be stored on computer.
Scanning : Digitising an image (e.g. photograph, logo etc.) so that it can be stored on
computer.
Scanner : The equipment used for scanning.
4.2 Data Capture
Data is being captured all the time and much of it ends up on a computer. These are
just some of the ways data is captured.
4.2.1 Data Capture Forms
If you open a bank account you have to supply your name and address and various
other details. The form you fill in is a data capture form. It is capturing data about
yourself.
If you buy a new radio you normally have to fill in a guarantee card in case something
goes wrong with it. This is another example of a data capture form.
The benefit of using a form is that the form is produced by the company so that data is
presented in a standardised form.
An enhancement to the basic data capture form is a form that is produced specifically
for you. If you belong to a book club your order form is pre-printed with your name
and address and your account number. When you return your order they know who
you are from the information already present on the form.
4.2.2 Questionnaires
You will often find examples of questionnaires in the High Street when you are
stopped by somebody and asked to answer a few questions.
Designing a good questionnaire is very difficult. Some of the points you need to bear
in mind are (and there are many others);
 What type of questions should you ask; multi-choice questions, questions where
the person being interviewed can give an opinion, questions which can have more
than one answer?
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Chapter 4 - Capturing and Inputting Data
 Who is the questionnaire aimed at? Are you likely to get bias results if you only
interview people aged between 18 and 30?
 Are the questions clear and unambiguous?
 Will the questions be asked personally or will they be sent through the post?
Q.4.2 Questions
Q.4.2.1 Collect five examples of forms that are designed to capture data. Say what you
think are the good and bad points about each form. Design your own form to collect
data about your classmates. How does your form compare to others in your class?
Q.4.2.2 Give three examples of data capture forms where the form has already been
pre-printed with details about yourself.
Q.4.2.3 Design a simple questionnaire and try it out on people at school (both students
and teachers). What problems did you encounter? What could you have done to
reduce these problems?
4.3 Inputting Data
Data Capture is closely related to Data Input. Some of the methods of inputting data
are explained below.
4.3.1 Using the keyboard
Using the keyboard is probably the most common method of inputting data into a
computer. If you write a letter on a Word Processor you will almost certainly use this
method.
4.3.2 Mouse
A mouse is almost as common as a keyboard due to the rise in popularity of Graphical
User Interfaces. You communicate with the computer by moving a pointer around the
screen and then clicking one of the mouse buttons to carry out some task.
Mice, typically, have two or three buttons.
4.3.3 Bar Codes
You probably have seen bar codes being used in supermarkets (you can also see them
on books and magazines).
Most goods you buy are marked with a bar code and these are scanned at the till. The
bar code identifies the goods and the computer returns the price you have to pay. Note
that the price is not part of the bar code otherwise every shop would have to charge the
same price.
The numbers that are represented by the bar code are printed underneath the code.
This is so the numbers can be input manually if the bar code cannot be read.
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Chapter 4 - Capturing and Inputting Data
4.3.4 Magnetic Strips
Magnetic strips are most commonly found on bank cards. If you look at the back of a
bank card you can see the strip. It holds information about the owner which is read
when it is inserted into the cash point (or swiped through a machine).
Magnetic strips are also used in other places and you are asked to consider these as
part of the questions.
4.3.5 OMR, OCR and MICR
OMR (Optical Mark Reading), OCR (Optical Character Reading) and MICR
(Magnetic Ink Character Recognition) are all examples where the data is read from a
form by the computer or by a document reader which is specially designed to do the
job.
 OMR reads marks made on a form and ‘understands’ the data because the mark
was made in a specific place on the form.
OMR is being used when you are asked to complete a multiple choice examination.
You may have thought that an examiner had to mark each form (if you had thought
about it at all). In fact the papers are probably being marked automatically using
OMR to check if you have made the correct choices.
 OCR is used to read hand-written characters and to try to understand what they
represent. It is quite a complicated thing to do.
To see why this is so, get ten of your friends to write down the same sentence and
look at the difference in the writing. It is difficult for a computer to interpret all of
these reliably. It is for this reason that you are often asked to use block capitals or
are given spaces in which to write each character.
 If you look at a cheque you will see a series of characters printed at the bottom. Not
only are they a strange shape but they are also magnetised. Being magnetic they can
be read by special equipment. This is an example of MICR.
The reason MICR is used is to reduce fraud. If normal characters, with normal ink,
were used it would mean that a fraudulent cheque was relatively easy to produce.
Not a good idea for a bank.
4.3.6 Touching the screen
Some screens allow you to point at them and the action taken by the computer
depends on where you touch the screen. To assist you to touch the right part of the
screen, pictures are often used to guide you to the correct area. You may have seen
this type of data input at Tourist Information Points or Railway Stations.
An adaptation of this method is touching the screen with a pen or ‘stylus’.
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Chapter 4 - Capturing and Inputting Data
4.3.7 Scanning
If you wish to store a picture (such as a photograph or a logo) on a computer the most
common method of inputting it is to scan it. This is done with a scanner that converts
the image into a form that can be stored on the computer. That is it digitises it.
There are two main types of scanners.
Hand-held scanners are moved across the picture. They are cheap and portable.
With a flat-bed scanner the image is laid on the scanner itself. These are more
expensive but allow better quality images to be captured.
Scanners are also used to read characters that are then processed by OCR software.
4.3.8 Human Speech
Human Speech is input to a computer via a microphone. The sound, like images, are
converted to a form which is suitable for storage on a computer.
4.3.9 Sensors
It is possible to have a variety of sensors connected to a computer. For example, a
thermometer could be connected which tells the computer the temperature. The
computer can use this information to control something like a central heating system.
Q.4.3 Questions
Q.4.3.1 Next time you are in your local town see how many different ways you can
find that retailers capture data.
Q.4.3.2 Apart from cheque and cash cards where else would you find a magnetic
strip?
Q.4.3.3 As long as you are aged sixteen or over you can go into thousands of shops,
pay one pound and see OMR in action. What would you be doing?
Q.4.3.4 Give one advantage and disadvantage of OMR, OCR and MICR
Q.4.3.5 Can you think of another type of input device that is commonly used to play
games?
R.4 Optional Further Research
R.4.1 Try to arrange a visit to a local company. Ask them how many different ways
they collect data from their customers.
R.4.2 A computer keyboard is often called a “QWERTY” keyboard. Why is this? And
why is a keyboard laid out this way?
R.4.3 How many keys on a computer keyboard actually display a character on the
screen when it is pressed? What are the other keys used for?
R.4.4 All books have an ISBN number which is represented as a barcode somewhere
on the book (normally on the back cover). What do the various parts of the ISBN
number represent?
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Chapter 5 - User Interface
Chapter 5 - User Interfaces
5.1 Definitions for this Chapter
User Interface : How a person communicates with a computer
Command Line Interface : A type of interface where the user types commands (via a
keyboard) to the computer.
Command Line Prompt : The characters which are displayed inviting you to type
something.
Graphical User Interface : A type of interface where a graphical interface is used.
The
interface normally consists of menus, icons (pictures) and windows. A mouse, as well
as the keyboard, is used to enter commands.
5.2 User Interfaces
The User Interface is the way in which you communicate with a computer and the way
the computer communicates back to you.
There are two main types of User Interface; Command Line Interfaces and Graphical
User Interfaces.
5.2.1 Command Line Interfaces
An example of a Command Line Interface is shown below. Explanations are provided
for the most important aspects of this interface.
This is a
command that
has been
typed in.
This is the
output of the
command
This is the
prompt, waiting
for the next
command to be
typed
This particular screen is showing the DIR command being used on an IBM compatible
PC. The DIR command gives a listing of files which match the file specification. In
this case it is any files with an extension of BAT.
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Chapter 5 - User Interface
5.2.2 Graphical User Interface
Graphical User Interfaces (GUI’s - pronounced Gooey) present the user with a
graphical representation that the user manipulates using the mouse and keyboard.
There are four main parts to a GUI; these being;
Windows. This is where information is displayed. Windows can be made bigger
and smaller and moved around the screen.
Icons. These are little pictures which the user can click on (with the mouse
pointer) to perform certain actions. For example, you might click on a printer icon
to print a document.
Menus. Windows may optionally have menus. They are normally situated across
the top of the window and they drop down when you click on them. (Note that
Acorn machines, which you may have used, have pop up menus which appear
when you click another mouse button).
Pointer. This is an arrow on the screen which represents the mouse. When you
move the mouse the pointer moves. To perform an action you move the pointer to
the relevant part of the screen and then click the mouse.
Here is an example of a Graphical User Interface. In fact it was the GUI being used
whilst writing this book
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Chapter 5 - User Interface
Icon
Menu
Window
Pointer
Q.5.2 Questions
Q.5.2.1 What do you consider the main advantages of a GUI over a Command Line
Interface?
Q.5.2.2 If you have access to an IBM compatible PC go to the Command Line
Interface (the DOS Prompt) and try these commands. What do they do?
i DIR
ii CLS
iii COPY C:\AUTOEXEC.BAT MYFILE.BAT
iv PROMPT $T
(Note : You may not be allowed access to the DOS prompt. In which case you will be
unable to do this question)
Q.5.2.3 GUI’s are sometimes called WIMP environments. Why do you think this is?
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Chapter 5 - User Interface
R.5 Optional Further Research
R.5.1 See if you can arrange a visit to a local company which uses a variety of
computers. Identify how many different types of User Interface they use and classify
them into Command Line Interface and GUI’s
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Chapter 6 - Outputting Data
Chapter 6 - Outputting Data
6.1 Definitions for this Chapter
Output Device : A device that receives an electrical signal and converts it to data or
information.
Pixel (Picture Element) : The smallest unit of information on a monitor.
Resolution : The amount of detail (number of pixels) on a monitor.
Screen Mode : The mixture of colours, resolution and text/graphics allowed on a
monitor.
Dot matrix printers : Printers which make up the image on the page by pushing pins
against a ribbon to make a series of dots.
Ink jet printers : Printers which squirt dots of ink at paper to make up the dots.
Laser Printers : Printers which use a laser to produce the image.
Impact/Non-Impact printers : Impact printers make contact with the paper. Non
Impact printers do not.
Character Printer : Printers which print a character at a time.
Line Printer : Printers which print a complete line at a time.
Page Printer : Printers which produce and print a complete page at a time.
Draft Quality : A mode of printing which produces lower quality output but at a faster
speed.
NLQ (Near Letter Quality) : A mode of printing which produces high quality output
but at a slower speed.
Plotters : An output device which is normally used to produce line drawings such as
plans for a house.
Microfiche : Reduced images of pages held on plastic.
It could be argued that computers are useless unless we are able to see the results of
what they produce. After all why bother collecting data, entering it into the computer
and performing various processes on that it if we cannot see the end result.
The first part of this chapter (6.1) will consider what an output device is and suggest
some devices in everyday use.
The remainder of the chapter will look at output devices that are typically connected
to computers.
6.2 What is an output device?
Calculators, telephones, faxes, supermarket tills (for receipts), hi-fi speakers and train
ticket machines are all output devices. In the context of Information Technology an
output device is something which receives an electrical signal and produces data or
information.
All of the above produce output which we regard as information.
Output which does not have meaning is said to be data (see chapter 2). A computer
controlling a robot would output data. The data would be fed to the robot which it
would interpret as an instruction to do something.
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Chapter 6 - Outputting Data
Q.6.2 Questions
Q.6.2.1 Give examples of two output devices - one which produces information and
one which produces data. Do not use examples given in the text and do not use
computer output devices.
6.3 Monitors
Monitors are the most often used computer output devices. In fact, a computer without
a monitor is very unusual (although possible).
6.3.1 Pixel
The picture on a monitor is made up of pixels (which is short for picture elements). A
pixel is the smallest element on a monitor. It is just like a newspaper photograph
which is made up of dots. The dot is the smallest element in the picture.
6.3.2 Resolution
The amount of detail that can be displayed on monitor is called its resolution. This is
normally measured as the number of pixels it can display. A typical number is 640
pixels by 480 pixels.
Some computers allow you to change the resolution. If you use high resolution you
have greater detail but it takes more memory to store the image. A lower resolution
results in loss of detail but you do not use as much memory.
6.3.3 Screen Modes
The number of colours you want to display affects how much memory the computer
needs to store the image. For example, it takes more memory to allow for 256 colours
as opposed to sixteen colours.
You can also decide if you only want to display text, graphics or both.
Deciding on the number of colours and whether you want graphics, or just text, allows
you to have various screen modes. For example one screen mode might allow sixteen
colours, in medium resolution with a graphics display. Different screen modes will
allow different mixes of colours, resolution and text/graphics.
Q.6.3 Questions
Q.6.3.1 Teletext is an example of a screen mode. Would you say that a teletext display
needs a high, medium or low resolution monitor? Explain your answer.
6.4 Printers
If monitors are the most common output device then printers come a close second.
Printers can be classified into three types; dot matrix, inkjet and laser printers.
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Chapter 6 - Outputting Data
6.4.1 Dot Matrix Printers
Dot matrix printers work by pushing small pins against a ribbon which, in turn, makes
contact with the paper.
The pins are arranged in a column. Older printers have nine pins to a column. More
modern printers have 24 pins to a column. As the print head (the print head holds the
pins) moves across the page the correct character can be printed by firing the pins in
the correct sequence.
Good quality graphics can be printed (especially with 24 pins printers), although dot
matrix printers tend to be slow and noisy.
6.4.2 Ink Jet Printers
Dot matrix printers are called impact printers as the print head actually makes contact
with the paper (albeit through the ribbon). Ink jet printers are non-impact printers.
Instead of making contact with the paper they spray fine jets of ink at the paper. The
dots they produce make up the required characters.
Instead of having a ribbon, an ink jet printer has a bottle of ink. By putting in a
different colour ink bottle you can easily get colour. Some ink jet printers have space
for more than one bottle of ink so more than one colour can be printed at the same
time.
6.4.3 Laser Printers
Laser printers, as their names suggests, work via a laser. Ink (or toner as it is more
correctly called) sticks to a light sensitive drum where a laser has touched it. The toner
is then transferred to the paper.
Laser printers can produce high resolution images. Typically they produce 90,000 dots
in a square inch (300x300). This is known as 300 dpi (dots per inch). 600 dpi laser
printers are not uncommon these days.
Q.6.4 Questions
Q.6.4.1 Imagine you are a 24 pin dot matrix printer. Using graph paper show how you
would print an “m”, an “a” and an “!”.
Q.6.4.2 A printer can either be considered a character printer (where one character is
printed at a time), a line printer (where a complete line is printed at a time) or a page
printer (where a whole page is printed at a time). Classify a dot matrix printer, an ink
jet printer and a laser printer into each of these categories.
Q.6.4.3 Many printers have two modes of operation; draft quality and letter quality
(sometimes called Near Letter Quality or NLQ). After reading the definitions at the
beginning of this chapter how do you think the two modes might be implemented on a
dot matrix printer and a laser printer?
6.5 Other Output Methods
6.5.1 Plotters
Plotters are most often used for applications which require some form of line drawing,
for example; maps, diagrams, plans etc. They usually have a pen which moves over a
fixed piece of paper. Different colours are produced by using different colour pens.
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Chapter 6 - Outputting Data
6.5.2 Microfiche
Microfiche stores images of paper on a plastic film. The images are held in a much
reduced form and you can easily fit thirty pages on one sheet of microfiche which is
about fifteen centimetres squared.
You might be able to see a sample of microfiche in a book shop where they sometimes
hold all the books in print on this medium in order to answer customer queries about
books in print.
A special reader is needed to look at pages stored on Microfiche.
R.6 Optional Further Research
R.6.1 There are various types of monitor (often called CGA, EGA, VGA, SVGA etc.).
Find out the characteristics of each one with regards its resolution, the number of
colours it can be display and the modes in which it can operate.
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Chapter 7 - Storing Data
Chapter 7 - Storing Data
7.1 Definitions for this Chapter
Main Store : Any Storage that is directly accessible by the CPU; normally RAM and
ROM.
Backing Store : Any storage that is external to the CPU (typically discs).
Read : The process of reading data from backing store and making it available to the
CPU.
Write : The process of writing data from the CPU to backing store.
Access Time : The time taken to read a piece of data requested by the CPU and
making it available for processing.
Direct Access : The ability to access a piece of data directly without having to read
preceding data.
Sequential Access : Accessing data in a serial manner. If data is at the end of a file
you
must read all the other data first.
Magnetic Tape : A sequential access backing store device that is normally used to
take
security copies of data.
File : Data or programs that are held on backing store, such as a disc. A file is given a
unique name.
Directory : A method of grouping like files together. When you place a file on a disc
you specify which directory it is to be stored in.
Security : Taking a copy of important files so that you can use it should something
happen to the original.
In Chapter 3 we discussed RAM, ROM and Discs. It might be worth reviewing this
chapter before starting this chapter.
7.2 Storage
In chapter 3 we briefly looked at some types of storage. In this chapter we will take a
closer look at storage.
7.2.1 Main Store
The main store of a computer is also known as main memory. It is the storage that is
directly available to the CPU. In a typical computer the main store is in the form of
RAM and ROM.
7.2.2 Backing Store
Backing store is any type of storage that is not directly available to the CPU. For the
processor to act upon any data it must be in main store. Therefore, if the CPU needs
some data that is on backing store it must first be loaded into main store.
The time taken to do this is known as the access time.
You should be able to appreciate that the computer will work faster if the data is
already in main store as it does not have to be retrieved from backing store. In addition
the main store is faster than backing store.
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Chapter 7 - Storing Data
The problem is that main store is more expensive than backing store. Therefore there
is time/cost trade-off when designing or buying a computer.
In chapter 3 we have already talked about three types of backing store (Hard Disc,
Floppy Disc and CD-ROM). If you have not done so already try to have a look at each
of these types of discs.
I am sure you have all seen a CD-ROM. Many people have them at home as part of
their hi-fi system. The CD’s used on computers are exactly the same. In fact you can
play your music CD’s on a computer.
Floppy discs are common place these days and there are probably hundreds within
your school. Can you see where the data is stored?
A hard disc is more difficult to see. You may have to ask somebody to take the lid off
a computer (do not do it yourself - it can be dangerous). To be honest, they are not
much to look at; just a metal case with a few wires sticking out.
A further type of backing store is magnetic tape. This is similar to a tape recorder but
it is connected to the computer and records data rather than music or speech.
Magnetic tape is normally used to take security copies of data which is then held away
from the computer in case there is a disaster.
If your school has a large number of computers there is a high probability that the data
is regularly backed up onto a magnetic tape. The tape should then be stored away from
the computers or placed in a fire proof safe. This means that if there is a problem with
the computer the data is secure and can be re-loaded when the problem is fixed.
Q.7.2 Questions
Q.7.2.1 How many characters can you store on a 3.5” High Density Floppy Disc?
How does this differ from a 3.5” Double Density disc? (Note : this question requires
research by the student).
Q 7.2.2 Using your knowledge of storage devices what do you think is the best
medium for the following types of data;
i. A large application distributed to a great many people.
ii. An Operating System.
iii. A weekly security copy.
iv. A copy of a file that you need to take home.
v. A letter that you are writing to your friend.
7.3 How a disc works
It’s okay saying “data is stored on a disc” but how does a disc work?
Inside the protective covering of a floppy disc there is a piece of plastic that can be
magnetised. A read/write head moves over the surface of the disc and either reads the
magnetic fields or produces a magnetic field which writes data to the disc.
Of course there must be some structure to the data so that the computer knows where
to find a certain piece of information.
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Chapter 7 - Storing Data
This diagram helps explain how a disc is structured.
Data is stored on
concentric rings called
tracks
The Disc is a piece
of plastic which
can be
magnetised)
Tracks are divided into
sectors which actually
store the data
You can see that a disc is divided into concentric rings called tracks. Each track is
further divided into sectors. Each sector can typically hold 512 characters.
If the CPU needs data from a disc it can be accessed be specifying the track and the
sector where the data has been placed. Similarly, data is written to a disc by specifying
the sector and track number where the data is to be written to.
7.4 Accessing Storage
There are two main ways you can access the data held on a storage device.
7.4.1 Direct Access
A direct access storage device allows immediate access to any piece of the data
without having to read all the data which comes before it.
Discs and main store are both examples of direct access devices.
7.4.2 Serial Access
With a serial access device you have to read all the data until you find the data you
require. Magnetic tape is an example of such a device. With a magnetic tape you have
to start at the beginning of the tape and read down the tape until you come to the data
you require. There is no way to ‘jump’ (directly access) any one piece of data on the
tape.
In some cases data held on a disc must be accessed in a serial (sometimes called
sequential) manner. This is because there is no information stored about the file which
enables the CPU to work out where a particular piece of data has been placed on the
disc; that is, its track and sector number.
Q.7.4 Questions
Q.7.4.1 Would you consider a CD-ROM a direct access or a serial device?
Q.7.4.2 Give one advantage of a direct access device and one disadvantage.
Q.7.4.3 Give an example where direct access would be more suitable over serial
access.
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Chapter 7 - Storing Data
7.5 Files
7.5.1 What is a file?
Up until now we have been talking about storing data on discs and tapes. We have
also looked at how data is actually stored on a disc. But there is one more thing we
need to consider: the concept of a file.
If we first consider a non-computer system it may be easier to explain what a file is.
If you take a look at your school work you will find it is partitioned into various
subjects such as English, French and Maths. For each of these subjects you probably
have a book that you use for your notes, following examples and carrying out
exercises set by the teacher.
Each of these books could be considered a file. That is it holds information (and data)
about one particular thing.
A computer is no different. If you write a letter you save it in a file. That is you give it
a name and it is stored on a disc using that filename so that it can be identified later.
The program that you used to create the letter (the Word Processor) is held in a
another file. So it continues, with files being created for all the different types of
information and data you need to store. Each file is given a unique name so that it can
be identified later.
7.5.2 Directories
On a typical computer there will be hundreds or (more likely) thousands of files.
Although each one has a unique name it can still be difficult to find one particular file
when you need it. Directories help in organise our data. It groups together files that
have a common theme; for example all our Word Processing files or all our programs.
The way you group your files together is largely a matter of personal preference,
although when you install certain programs they will automatically set up their own
directories.
The screen shot below shows a number of directories. Note that there are various ways
of displaying directories on a computer. This just demonstrates one method.
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Chapter 7 - Storing Data
The top-level (or root directory) is the one labelled ‘C:\’. This has a number of subdirectories beneath it including ‘accounts’, ‘acroread’ and ‘agenda’.
In addition the ‘accounts’ directory has further sub-directories; these being ‘gk’, ‘hk’
and ‘house’.
Each of these directories can contain files within them. The screen shot above shows
that the ‘acroread’ directory has been selected. The right hand side of the screen shows
the files that are in this directory.
Also note that you can have a file with the same name as long as it is in a different
directory. This is because the directory name forms part of the unique name which
identifies the file.
7.5.3 Structure of a file
Every file that you create has some sort of structure to it. This is obvious when you
think about it. A Word Processor file, for example, has to have a certain structure so
that it knows where to find information about your document such as where a new
paragraph starts and where you want a new page to begin.
This is known as the internal structure of the file. As a user of the Word Processor you
do not need to know anything about this internal structure. That is the job of the
program you are using.
But there is also another structure to a file that is particularly apparent in a program
such as a database. This is the logical structure of the file. This means it is the
structure that you see when you use the program. The way it is stored - its internal
structure - might (and probably is) completely different.
We will look at the logical structure of a file when we consider databases in chapter
10.
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Chapter 7 - Storing Data
Q.7.5 Questions
Q.7.5.1 The directory structure shown in 7.5.2 can be represented as a tree structure.
Draw a tree that represents this structure.
7.6 Security of files
7.6.1 Why do we need to secure files?
If we are holding data on computer we need to take certain steps in order to ensure
that the data is secure. Some of the reasons why we need to do this are outlined below.
 The hard disc holding our data might become corrupted. For example, the disc
might become damaged so that data cannot be read from it.
 You might accidentally damage a disc. For example, you might spill a cup of
coffee onto a floppy disc or delete a file that you actually need.
 The computer might suffer a disaster such as fire or flood.
 Somebody might destroy the data deliberately. This could be done by physically
damaging the data or by planting a software version of such vandalism, often called
a virus. Alternatively the computer might be accessed by somebody who is
unauthorised to do so. These people are known as hackers.
 A file might be updated incorrectly so that you need to have a previous version
available in order to apply the correct processing to it.
7.6.2 Securing Files
In order to protect ourselves against the dangers outlined above it is important to take
copies of files on a regular basis. This means we have two copies so that if something
is wrong with the original copy we have another copy we can use.
It is also important to keep the security copy of the file away from the computer which
holding the original file.
There are many ways to copy files. Users who have a lot of data to secure will
probably copy all the data to magnetic tape on a regular basis.
Users which have only a small amount of data will often use floppy discs to hold their
security copies.
There are many programs available that will do your security for you. Some will even
do the security at a certain time each day so that you do not forget.
In addition, some programs allow you to compress the data as it is secured. This
means that the security copy occupies less space than the original file. If you need to
use the security copy you will need to expand the data before it is used.
Q.7.6 Questions
Q.7.6.1 Why is it important for a security copy of a file to be stored away from the
computer which has the original file on?
Q.7.6.2 Can you think of a disadvantage of compressing data as you take the security
copy?
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Chapter 7 - Storing Data
R.7 Optional Further Research
R.7.1 There are various types of floppy disc. Find out about the different types and
how much data each can hold. Note that floppy discs have been available in at least
two other sizes other than 3.5”.
R.7.2 If your school uses a magnetic tape to backup data find out how frequently the
back ups are taken, where they are stored and what, if any, tests have ever been done
to ensure the data can be restored if necessary.
R.7.3 If you have access to a CD-ROM drive find out how much data can be stored on
a CD-ROM. Work out how many floppy discs you would need to store the same
information. Also work out if the data on the CD-ROM would fit onto the hard disc
installed in the computer.
R.7.4 When implementing a backup system you can use a method sometimes known
as archiving. Under this system you only secure files which have been created or
changed since the last security was taken. Investigate how such a system would work.
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Chapter 8 - Applications Software
Chapter 8 - Applications Software
8.1 Definitions for this Chapter
Program : Instructions to the computer that tell it what to do and in what order.
Programs are written by programmers in a computer language such as BASIC.
Software : The term used to describe all types of programs including the operating
system, applications software and programs written by the user themselves.
Applications Software : Software designed for a specific task, such as Word
Processing, which normally has a full set of documentation. Applications Software is
sometimes called a package.
Evaluation : Looking at software to see if it is suitable for the planned job.
Word Processing : A package that allows you to enter, edit and print text and,
optionally, a great many other things.
Database : An application that allows you to store and retrieve information.
Spreadsheet : An application that allows data to be stored in a table format and have
calculations performed on that data.
Graphics : An application that allows you to produce graphics such as bar charts, pie
charts etc.
Desk Top Publishing : An application that produces documents suitable for
publication.
Export/Import Data : Allows one application to produce data suitable for another
application (export). An application that reads such data ‘imports’ it.
Cut/Copy/Paste : Remove data from an application (Cut) or make a copy of it. The
data can then be pasted into another, or the same, application.
8.2 Software, Programs and Applications Software
8.2.1 Programs
So far in this book we have been referring to software and programs as if they are the
same thing. This is because there is a very fuzzy line between the two terms if, indeed,
such a line exists.
We can start by considering a program. A program is a sequence of instructions to the
computer. It tells the computer what to do and in what order.
A program is produced by a programmer who uses a computer language to tell the
computer what to do. Some examples of the languages used by programmers include
BASIC, FORTRAN, COBOL, C, C++ and LISP. There are many more.
8.2.2 Software
Software is a term used to describe programs. However software encompasses others
areas such as the Operating System and programs supplied by third parties but as this
software is still a sequence of instructions to the computer it can still be considered a
program. However when people refer to the Operating System, they normally call it
software rather than a program.
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Chapter 8 - Applications Software
8.2.3 Applications Software
Applications Software is a little easier to define. It is a collection of programs (or
software) that has been designed for a specific task. It normally comes with
documentation (often on CD-ROM these days) and support from the supplier.
For example, a Word Processor is a piece of applications software. It is a collection of
programs that allows you to manipulate words (and usually graphics as well). You
will receive some sort of manual that allows you to use the application. You may,
optionally, receive some sort of support arrangement that allows you to phone
somebody if you have a problem or query.
Applications software is often known as a package or simply an application.
Q.8.2 Questions
Q.8.2.1 Is RAM hardware or software?
8.3 Types of Application Package
In the next few chapters we will be looking at three specific applications (Word
Processing, Spreadsheets and Databases). However it is important to realise that there
are other types of applications packages.
8.3.1 Custom Designed Packages
You (or more likely a company) may have a specific requirement that needs a custom
built application to be written. For example, an insurance company might consider
that it needs to write a package that deals with all its business needs.
The package may be written by the company itself or it might use a software house to
write it for them.
The end result is a custom designed (and written) package.
8.3.2 Common Requirement Packages
Word Processing, Spreadsheets and Databases are the three most common uses for
computers but there are other packages which people and companies commonly need.
For example, many companies use a computer to send invoices and prepare their
accounts. There are packages you can buy which have already been written to carry
out these tasks.
Q.8.3 Questions
Q.8.3.1 What do you consider are the advantages and disadvantages of a custom
designed package as opposed to buying a package ‘off the shelf’?
8.4 Deciding which package to buy
In order to decide which application to buy or to use it has to be evaluated. This means
deciding which application is most suitable for the job you plan to do.
An insurance company, for example, might evaluate all the packages available before
deciding if it will write its own.
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Chapter 8 - Applications Software
To carry out the evaluation a company will compile a list of all the things that it needs
a package to do. Each package will then be compared against this list to see if it meets
the requirements of the insurance company.
They may also consider some of the following points as part of the evaluation;
 Is the package easy to use?
 Is it supported in case there are problems?
 Is it updated regularly to cope with things like changes introduced by the
government?
 Does the package come with manuals so that the users can refer to them?
 Is there a training course available to learn how to use the package?
 Can the package accept input from and output data to other packages used by the
company?
 Does the package run on the computers used by the company?
 Is the package reliable? For example, does it validate and reject invalid input?
The company may also go and see other companies that are using the package in order
to see it in action and find out if it has proved reliable.
Once the evaluation has been completed the insurance company will decide which
package to buy or whether to write their own package.
Q.8.4 Questions
Q.8.4.1 If you had to write an essay, what would you look for in a Word Processing
Package to assist you?
8.5 Some typical packages
In the chapters that follow we will be taking a closer look at some typical applications.
This section gives an introduction to the applications we will be looking at and
describes when you might use them.
8.5.1 Word Processing
A Word Processor is a package that allows you to enter, edit and print text. This book
was produced on a Word Processor.
Depending on the sophistication of the Word Processor you may be able to change the
font and size of the characters as well as perform other actions related to the text.
Some Word Processors include options that will check your spelling and even your
grammar. You may be able to send a personalised copy of the same letter to all of your
friends without having to type a separate letter to each of them (that is, mail merge).
You may also be able to include pictures and graphics amongst the text although this
is getting close to Desk Top Publishing which produces documents which are suitable
for publication.
8.5.2 Databases
A database allows data to be stored and retrieved. Once the data has been entered it
can be retrieved in a variety of ways. For example, you can retrieve it in some sort of
order (that is, sort it) or you can retrieve data that satisfies some criteria (for example,
all employees who earn over £12,000).
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Chapter 8 - Applications Software
8.5.3 Spreadsheets
A spreadsheet holds data in a table format; as a series of rows and columns. The cells
(as they are called) can be related in various ways. For example, one cell might hold a
cost price for a particular item. Another cell might hold the VAT rate in force at the
current time. Using the information in these two cells you can work out the retail price
of the product. If the cost price or the VAT rate changes then the retail price will
automatically change.
8.5.4 Graphics
A graphics application will produce various types of graphics based upon some data
that has been supplied. The data often comes from a spreadsheet or database.
Various types of graphics can be produced. For example a simple line graph or a pie
chart.
Q.8.5 Questions
Q.8.5.1 What package would you use for each of the following tasks?
i. Writing a report.
ii. Preparing company accounts.
iii. Keeping information about the products a company supplies.
iv. Keeping a class register.
Q.8.5.2 Give an example of a use for each of the applications describe above. Say why
the application is suitable.
8.6 Communication between packages
Many applications allow communication between itself and other applications. This is
commonly done by one of two methods.
8.6.1 Importing and exporting
One application is able to accept data that has been produced by another application.
That is it can import data. To be able to import data the sending application has to be
able to export data. That is produce data in a format that another application can read.
8.6.2 Cut/Copy/Paste
Within an application you can often highlight a section of the data and then copy the
data . This makes a copy of the data in a reserved area (on some systems this is known
as the Clipboard or Clipbook). You can now switch to another application and do a
paste. This copies the previously copied data into that application.
You can also use cut instead of copy. This removes the data from the original
application but still makes it available to the other application.
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Chapter 8 - Applications Software
R.8 Optional Further Research
R.8.1 Being able to communicate between packages via the export/import method
often involves using special file formats. Investigate and experiments with the
following file formats; Rich Text Format (RTF), Comma Separated Variables (CSV)
and ASCII text (TXT).
R.8.2 DDE and OLE are yet other ways of using data from one application in another.
Find out what these terms mean and investigate how they work.
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Chapter 9 - Word Processing
Chapter 9 -Word Processing
9.1 Definitions for this Chapter
Word Wrap : The way a Word Processor automatically keeps words on the same line
without splitting them.
Font : A set of characters of a particular size and design.
Margin : The limits at which you are allowed to print text on a page.
9.2 Introduction to Word Processing
9.2.1 A typical Word Processor
Word Processing is an application that allows you to enter, edit and print text.
This book was written on a Word Processor and you may be using a Word Processor
to look at it.
The following screen shot shows what a typical Word Processor looks like.
You can see that the Word Processor is running in a GUI environment (see chapter 5).
The main part of the screen is where text is actually typed. You can see part of this
chapter within the window.
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Chapter 9 - Word Processing
9.2.2 Entering Text
To enter text you simply type and the text appears where the cursor is positioned (you
can see the cursor in the above screen - it is the black line just above ‘9.2’).
When entering text you simply keep typing until you reach the end of a paragraph.
You only press the ‘ENTER’ key when you reach the end of a paragraph. You do not
(and should not) press the ‘ENTER’ key when you are nearing the end of a line as the
Word Processor will automatically ‘word wrap’ onto the next line. This means that if
there is not enough space to fit a word onto the end of the current line the entire word
is placed on the next line. This means you do not have half of a word on one line with
the remainder on the next line.
9.2.3 Common features
The menus and toolbar (the little pictures below the menu) are there so that you have
access to the various facilities within the Word Processor. Some of the common
facilities are described below.
 You can underline text; like this
 You can make text bold; like this
 You can make text italic; like this
 You can change the font style and the size of text;
 You can centre text on the page; like this
 You can combine these different styles;
font and size).
(underline, bold, italic, different
9.2.4 Other Features
Some Word Processors will include features such as Spell Checking. If the Spell
Checker finds a word it does not recognise it will suggest words that you might
choose to take its place. If you select one of these words it will automatically replace
the incorrectly spelt word.
Here is an example of a spell checker in action.
The word ‘schol’ was spelt incorrectly. When it was spell checked it suggested that
the word be changed to ‘school’. We were also given a number of other words we
could use instead.
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Chapter 9 - Word Processing
The buttons on the right (Ignore, Ignore All, Change etc.) allow us to decide what to
do.
Word Processors contain many other features. Some will even check your grammar
and even allow you to type in a word and have it suggest alternatives; that is a
Thesaurus.
Q.9.2 Questions
Q.9.2.1 Using any Word Processor you have access to write at least three paragraphs,
with each paragraph occupying at least three lines. Make use of bold, italics and
underlining. Also use different fonts and sizes. Print the document.
Q.9.2.2 Type the word ‘windws’ (windows without the ‘o’) into a Word Processor.
Spell check it. What suggestions are you offered as a replacement word?
9.3 Margins
A piece of A4 paper is 21cms wide and 29.7cms high but when you print you do not
print right to the edge of the paper. It is the margins that dictate how far in from the
edges you print.
There are various ways to set margins. One method is to use a dialogue box; like this
This particular dialogue sets the margin for a complete document. You simply change
the values for the relevant margins (e.g. the left and right).
Alternatively we can set margins for individual paragraphs. This is done in a similar
way but only affects the selected paragraphs.
Note that the Word Processor you use might have a different way of setting the
margins but the result will be the same.
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Chapter 9 - Word Processing
9.4 Indents
Closely related to margins are indents. This is a method of formatting a
paragraph so that the first line of the paragraph is indented. Like this paragraph.
Alternatively the second, and subsequent, line can be indented. This means the
paragraph will look like this. Can you see the difference between the two.
To set indents you can often use a dialogue box similar to that shown above. But you
may also be able to use the ruler. This is an area on the screen that is dedicated to
changing the layout of the page. This screen shot shows a ruler.
This is the ruler. You can “drag”
this to change the margin or indent
Q.9.4 Questions
Q.9.4.1 Using the document you created in Q.9.2.1 change it so that the right and left
hand margins are 1cm less than they were originally. Also change the paragraphs so
that the first lines are indented by a further 2cm. Print the document.
9.5 Tabs
Pressing the ‘TAB’ key (normally the key above ‘Caps Lock’) is a method of
arranging text on the page. By pressing the tab key you can jump a certain number of
spaces. Typically this is five but you can define your own tabs so that you jump as
many spaces as you want.
Tabs are useful for creating simple tables and should be used in preference to multiple
space characters.
9.6 Blocks of text
When working with a Word Processor you often need to work with whole sections of
text. For example, you might need to delete a paragraph, move a page or copy a
couple of sentences. To do this, Word Processors allow you to highlight a section of
text and then work with that section.
If your Word Processor allows you to work with a mouse you usually highlight text by
clicking and dragging. Once the text is highlighted you can perform the relevant
operation on it.
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Chapter 9 - Word Processing
Q.9.6 Questions
Q.9.6.1 Using the document you created in Q.9.4.1 move the third paragraph so that it
becomes the second paragraph. Print the document.
R.9 Optional Further Research
R.9.1 It was stated in the text that tabs should be used in preference to multiple spaces.
Why is this? Hint : It has to do with proportional fonts.
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Chapter 10 - Databases
Chapter 10 - Databases
10.1 Definitions for this Chapter
Data File : Consists of a collection of records.
Record : A collection of fields which relate to one subject, for example all the details
about one of your friends.
Field : Part of a record that holds one item, e.g. a name, an address, a phone number
etc.
Key : A field which uniquely identifies a record
Database : A large file(s) containing related information which can be accessed in a
variety of ways.
Query : Specifying to a database program a set of conditions. The records which
match the criteria are returned.
Expression : Something which returns a single value. This can be a number, a string
or
a value such as TRUE or FALSE.
Logical Operators : Terms such as AND, OR and NOT which can be used within a
query to make a single expression.
Information Retrieval : Retrieving the information you require (normally via a query)
from stored data (usually a database).
10.2 What is a database?
Before we look at a computer database let’s just consider what a database is when it is
not stored on a computer.
A telephone directory is a database. The directory itself can be considered a data file.
It is a file that contains related information. The information consists of names,
addresses and phone numbers, for all the people in a particular area.
The directory (or data file) is split up into a number of records. In this case each record
consists of a persons name, their address and their phone number.
The individual parts of a record are called fields. In our telephone directory there are
three fields; name, address and phone number. Each field will have a data type
associated with it (see Chapter 2).
One of the fields will be designated as the key field. This is the field that uniquely
identifies each record. In the questions for this chapter you are asked to consider what
is the key field for a telephone directory.
To summarise, a database consists of a data file, the data file contains records, each
record has a number of fields; one of which is the key field.
The terms datafile and database are almost identical in meaning but the definition of a
database is that the data can be accessed in a variety of ways. With a telephone
directory you can only access the data using somebody’s surname. If the file was
stored on computer it would be possible to search the data to search for a number to
see who it belonged to. Of course, the same search is possible with a telephone
directory but it would be much too slow to be of practical use.
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Chapter 10 - Databases
Q.10.2 Questions
Q.10.2.1 What is the key field in a telephone directory?
Q.10.2.2 For a school register say what is the datafile, the records, the fields and
which field is the key field?
Q.10.2.3 Give three examples of when it would be sensible to use a computerised
database?
10.3 Setting up a database
10.3.1 Deciding upon and setting up the database structure
Let us assume that we want to set up a database to hold information about all the
people in the school.
When we are setting up a database the first thing we have to do is decide what type of
data we want to keep. Here is a list of the data we might want to hold (you would
probably want to keep more).
Field Name
Data Type
First Name
Surname
Date of Birth
Phone Number
Class Number
Text(30)
Text(30)
Date
Text(15)
Numeric
In deciding on our data we have already made some important decisions. We have
named each field and decided which data type we will use to represent it. We can now
enter this information into the database so that it knows what type of data to expect.
An example of this having been done is shown below.
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Chapter 10 - Databases
10.3.2 Collecting the data
Now we have decided on the data we want to keep we need to actually collect it. For
our example it is quite an easy process. The school probably has this information
already. We just need to collect it altogether so we can enter it into our database.
But you may need to find other ways in order to collect the data. For example, you
may want a field that holds information about each persons interests or hobbies. To
collect this you may need to send out a questionnaire.
Some ideas for collecting data were outlined in Chapter 4.
10.3.3 Entering the data
Once the database has been set up and the data has been collected we can enter it into
the database.
You will enter the data one record at a time. Carrying on with the example we started
above you may end up with a database that looks like this (though, in real life, there
would be more records).
First Name
John
Michael
Jane
Michele
Mark
Surname
Brown
Smart
Smithers
Sheet
Dempster
Date of Birth
21/07/83
19/08/83
20/03/83
06/04/83
09/07/83
Phone Number
01987-12345
01987-12303
01962-87614
01962-81762
01987-51482
Class Number
23
14
23
23
14
Once you have entered the data you can add new records, delete records and edit those
that are already in the database.
Q.10.3 Questions
Q.10.3.1 If your school identified its classes by cathedrals (e.g. Salisbury, Canterbury
etc.) what change(s) would need to be made to the database definition shown above
(section 10.3.1).
Q.10.3.2 Create a computer database that holds data about everybody in your class.
Decide for yourself what data you want to keep. Next collect that data in whatever
way you feel is appropriate, set up the database using appropriate data types and then
enter the data you have collected.
Produce a print of the database records and also a print showing the database
structure. Also hand in your data collection documents.
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Chapter 10 - Databases
10.4 Using a database
Once we have our database we can use that data in various ways.
10.4.1 Sorting
A database allows you to sort the data so that it appears in some sort of order. For
example, we could sort the small database we have been looking up so that it appears
in Surname order. Our database will now look like this.
First Name
John
Mark
Michele
Michael
Jane
Surname
Brown
Dempster
Sheet
Smart
Smithers
Date of Birth
21/07/83
09/07/83
06/04/83
19/08/83
20/03/83
Phone Number
01987-12345
01987-51482
01962-81762
01987-12303
01962-87614
Class Number
23
14
23
14
23
Of course, we can sort on any of the fields. Depending on what you want to use the
database for, it may be sensible to sort the database on the Class Number.
10.4.2 Querying
One of the most powerful features of a database is the ability to ask it questions or
perform queries.
As an example we might want to ask the database to show us all the records for class
23. We would be returned the following records.
First Name
John
Michele
Jane
Surname
Brown
Sheet
Smithers
Date of Birth
21/07/83
06/04/83
20/03/83
Phone Number
01987-12345
01962-81762
01962-87614
Class Number
23
23
23
To ask a query we enter an expression. This is something which returns a single value.
In the example given above the expression would be ‘Class Number = 23’. This is an
expression which returns a value of TRUE or FALSE. If TRUE is returned the record
is displayed. If FALSE is returned the record is not displayed. Therefore ‘Class
Number = 23’ is FALSE for class 14 so these records are not displayed.
In the database used to produce these examples the query to show all students in class
23 is entered in a window like this:
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Chapter 10 - Databases
It is possible to add simple expression together to form more complex queries. This is
done using logical operators.
For example, you could ask to see all students in class 23 with a surname of Smith.
The expression for this would be ‘Class Number = 23 AND Surname = Smith’. The
AND is a logical operator. It says that both simple expressions must be TRUE for the
entire complex expression to be TRUE.
Other logical operators include OR and NOT.
10.4.3 Printing
If we have taken the trouble to sort our database and perform queries to extract the
information we require it would seem sensible to be able to print it.
As well as printing all the records of the database it is also possible just to print the
results of a query. Examples of these types of print have been shown above.
It is also possible to only print certain fields. You may want to create a telephone list
from the database. This requires all the records to be printed but only the Surname,
First Name and Telephone Number. We do not require the Date of Birth or the Class
Number.
The telephone list would look like this.
Surname
Brown
Dempster
Sheet
Smart
Smithers
First Name
John
Mark
Michele
Michael
Jane
Phone Number
01987-12345
01987-51482
01962-81762
01987-12303
01962-87614
Notice that we have also moved the Surname field so that it is the first field. This is
because you would expect a telephone list to appear in this format.
Q.10.4 Questions
Q.10.4.1 Using the sample database we have developed in this chapter what
expression would you use to search for anybody in class 18 or for anybody with a
surname of ‘Jones’.
Q.10.4.2 Using the database you created in Q.10.3.2 sort the data on one of the fields,
carry out a query and produce a print which does not show all the fields. Hand in three
prints showing the results. Also provide a brief description of the field you sorted on
and the query you did.
R10 Optional Further Research
R.10.1 There are many types of database. Two of the most common are a ‘flat-file
database’ and a ‘relational’ database. Investigate the differences between the two and
make a list of advantages and disadvantages. Which one do you consider best?
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Chapter 11 - Spreadsheets
Chapter 11 - Spreadsheets
11.1 Definitions for this Chapter
Model : A simulation of something so that it behaves like the real thing.
Spreadsheet : A type of program that gives you a table on the screen. You can enter
various types of data into a spreadsheet and make relations between the data.
Cells : A spreadsheet is made up of rows and columns. The point at which a row and
column meet is called a cell. A cell is referenced by its row and column. You enter
data
into a cell.
Formula : A formula is typed into a cell. It is used when you wish to work out the
value for that cell from the values in other cells.
Relative Reference : A relative reference changes when the cell is copied. That is the
cell reference is relative to its position on the spreadsheet.
Absolute Reference : An absolute reference stays the same, even if the cell is copied.
11.2 Models
11.2.1 What is a model?
Before we look at spreadsheets we are first going to consider the term model, as a
spreadsheet is a good example of a model.
You will already be familiar with the term model either from its use on the catwalk or
when it is used to describe something that looks like another object. For example, you
could build a model of a Formula 1 racing car.
When creating a model on a computer we are doing something that is not too far
removed from building a model of the racing car.
We take a real life situation and model it on the computer. A good example, especially
for this chapter on spreadsheets, is the financial accounts for a company. If we use a
spreadsheet to ‘do the accounts’ we are modelling the accounts on the computer.
The accounts actually exist as part of the business. We are simply modelling them on
the computer.
Although this chapter is mainly about spreadsheets, models are not just applicable to
that type of application. Other examples of models are;
 A Space Invaders type game. This models a world where earth is being attacked by
aliens.
 A car assembly plant that is automated by robots. The computer will have a model
of the robot programmed into it.
 The database we developed in the last chapter. This models the students in a
school.
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Chapter 11 - Spreadsheets
11.2.2 Why use a model?
There are many reasons for using a model. Some of these reasons are as follows:
 A model can be made to go faster than real life so we can predict what is going to
happen; for example a weather forecast.
 You can ask ‘what if’ questions. If you have modelled a company on a spreadsheet
you can ask what will happen to your profits if you sell less products in the first
quarter next year?
 You can experiment without danger. In a car racing simulation it does not matter if
you crash.
 It can be cheaper. The Army may use a tank simulator to train their drivers rather
than risk using a real tank and have it damaged.
 It can give people access to things they could never do in real life. A museum could
model a rare book on computer so that everybody could look at it. The actual book
could not be handled by so many people.
 Systems such as road traffic in a town or the ‘Big Bang’ theory can be modelled to
see if we understand how they work by seeing if the model acts in the same way as
the real thing.
11.2.3 Disadvantages of using a model
The main disadvantage of using a model is that it does not know everything about the
situation you are modelling. Your company accounts will not know what will happen
to interest rates. In a Virtual Reality game you may only have feeling in your hands as
that is the only place on your body where there are sensors which are connected to the
model.
Q.11.2 Questions
Q.11.2.1 Think of three situations which are models of the real world. Where does the
model differ from the situation it is modelling?
11.3 Spreadsheets
11.3.1 Introduction to Spreadsheets
A spreadsheet is often used to model situations which are based on numeric
data. Spreadsheets were originally designed for accountants and they are often
used to prepare company accounts (which is a model of the current state of the
finances of a company).
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Chapter 11 - Spreadsheets
When you use a spreadsheet you are presented with a table; like this:
Column
Cell
Row
1
2
3
4
5
A
January
B
C
D
56.71
123.57
The spreadsheet is made up of individual cells. In the spreadsheet above one of
the cells contains the value 123.57.
The cells are arranged in columns and rows. The columns go down the
spreadsheet. The rows go across the spreadsheet.
Each column is given a name. In the above example we have the columns A, B,
C and D.
Similarly the rows are given names (1, 2, 3, 4 and 5).
Using the row and column labels it is possible to reference any cell in the
spreadsheet. The cell which contains the value 123.57 is in the cell referenced
by B3.
A spreadsheet can hold three types of data:
1. Numbers. For example, 123.57
2. Text. For example, ‘January’
3. Formulae, which we will look at in a moment.
11.3.2 Sample Spreadsheet
Below is a sample spreadsheet. It models a school outing that is going to visit
Manchester United’s Old Trafford Football Ground.
A
1
2
3
4
5
B
C
D
School visit to Old Trafford Football Ground
Name
Brian
Dawn
Stephen
Amount to pay
65.00
65.00
65.00
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Paid so far
33.54
23.58
5.87
Left to pay
GCSE Information Technology
Chapter 11 - Spreadsheets
Notice the following points
 The main title has spread over its neighbouring cells. This is because there is
not enough space to fit everything into the cell A1.
 The column widths are different sizes. This is so that we can fit all the data
into the cell. For example, the ‘Name’ column is quite wide so that we can
fit in a long name. It is possible to adjust the width of any column.
 You can improve the look of the spreadsheet by using different sizes of fonts
and types of alignment.
For example, the title is printed in a font size of 14. It is also bold.
The column headings are centred within the cell and also printed in bold.
The rest of the spreadsheet is printed in the ‘standard’ font size.
 All the figures have been ‘formatted’ so that they print two decimal places. If
we did not do this a value such as 23.90 would show as 23.9 and the 65.00
value would show as 65.
 The figures have been ‘right aligned’ within the cells. This means they are
right up against the right hand edge of the cell. This has been done so that the
decimal points line up.
 We have not entered values into the ‘Left to pay’ cells. Later we will see
how to get the spreadsheet to work these out automatically.
11.3.3 Adding a formula
So far all we have done is entered data into the spreadsheet. We could achieve exactly
the same result with a Word Processor. So why use a spreadsheet?
A spreadsheet program gives us the ability to enter a formula into a cell. Let’s take a
look at an example:
If we type ‘=B3-C3’ into cell D3 the value 31.46 will appear in D3. This is because
we are using a formula.
A formula always starts with an equals sign (that is how the spreadsheet knows it is a
formula) and is followed by a mathematical expression. In this case it is saying “take
the value in cell B3 and subtract from it the value in C3”.
We can enter the same formula into D4 and D5 to work out how much Dawn and
Stephen still have to pay. But we must change the cell references so that we are
referring to rows 4 and 5.
Our spreadsheet, with the formulae displayed, would look like this:
A
1
2
3
4
5
B
C
D
School visit to Old Trafford Football Ground
Name
Brian
Dawn
Stephen
Amount to pay
65.00
65.00
65.00
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Paid so far
33.54
23.58
5.87
Left to pay
=B3-C3
=B4-C4
=B5-C5
GCSE Information Technology
Chapter 11 - Spreadsheets
This is what you would actually enter but the actual display would look like
this:
A
1
2
3
4
5
B
C
D
School visit to Old Trafford Football Ground
Name
Brian
Dawn
Stephen
Amount to pay
65.00
65.00
65.00
Paid so far
33.54
23.58
5.87
Left to pay
31.46
41.42
59.13
Because the ‘Left to Pay’ values are being calculated by a formula we can
change one of the other figures and the ‘Left to Pay’ figure will automatically be
updated.
For example, if Stephen pays another £20 we would change C5 to 25.87. D5
would automatically change to 39.13.
Just to emphasise that point, we do not have to change D5 in any way because it
contains a formula, it updates itself.
11.3.4 More on Formulae
In a typical spreadsheet application there are many types of formula you can enter. In
the above example we have just used subtraction. We could just as easily have used
addition, multiplication or division (although it would not make sense in the context
of what we are modelling).
We can also use functions. These are features of the spreadsheet that do slightly more
complex tasks than simple expressions.
Before we look at some of the common functions we need to look at how we refer to a
group of cells at the same time.
At the moment, all we have learnt is how to refer to a single cell (e.g. C4, B3 etc.) but
what do we do if we need to refer to all the cells from C3 to C5? To do this we specify
the two ends of the range separated (normally) by a colon. So to refer to cells C3 to C5
we use ‘C3:C5’.
Now we can look at some of the common functions.
SUM :
This is by far the most common function. It adds together the values in
the specified range. For example, if we entered ‘=SUM(B3:B5)’ in cell
B6 of the above spreadsheet the cell will display 195.00. This is exactly
the same as using the formula ‘=B3+C3+D3’ but it is shorter,
especially when the range of cells becomes large.
AVERAGE : Returns the average of the cells in the given range e.g.
‘=AVERAGE(C3:C5)’ would return 40.04
MAXIMUM : Returns the maximum value in the range. ‘=MAXIMUM(C3:C5)’
would return 33.54.
MINIMUM : The same as MAXIMUM but returns the minimum number.
Note that the name of the functions may be slightly different in the spreadsheet
you use. For example, MAXIMUM may be called MAX.
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Chapter 11 - Spreadsheets
11.3.5 Copying Cells
Up until now you may have been entering each formula into every cell that requires a
formula. There is an easier way.
You can enter a formula into one cell and then copy that formula into other cells that
require a similar formula.
In our example, if we enter a formula into cell D3, we can copy that formula and then
paste it into D4 (see 8.6.2 for a description of copy and paste). The spreadsheet
automatically changes the cell references in the formula from row 3 to row 4. This is
because it assumes you want to work on figures on the same row that the formula is
on. And this is nearly always the case.
These types of references are called relative references as the cell references change
relative to where they are on the spreadsheet.
There is another type of reference called an absolute reference. These references are
often specified in the format $C$5 (as opposed to C5). If you copy one of these
references the cell reference does not change.
This type of reference is useful if you have a fixed figure on your spreadsheet (such as
the VAT rate). No matter how many times you copy a formula you always want the
formula to point to the same cell to find out the current VAT rate.
Q.11.3 Questions
Q.11.3.1 Look at the Old Trafford spreadsheet in 11.3.2 above and answer the
following questions:
 What value is in cell C4?
 In what cell is the value ‘Paid so far’?
Q.11.3.2 Using a spreadsheet package of your choice set up the Old Trafford
spreadsheet as shown in 11.3.2. Try to match the formatting as closely as possible.
Hand in a print of the result.
Q.11.3.3 Using the spreadsheet you produced in Q.11.3.2 answer these questions.
 Enter some text into cell B2. What happens and why?
 Increase the font size of ‘Amount to Pay’ by at least four points. What happens and
what can you do to correct it?
 Change the format of the cells which display numeric values so that a pound sign is
automatically displayed (e.g. entering 52.34 is displayed as £52.34). Why is it
important not to enter the pound sign when typing in the figures?
Q.11.3.4 Using the spreadsheet you have been developing, use the SUM function to
show how much all the students have paid so far and how much is still outstanding.
Produce a print.
Q.11.3.5 What is the benefit of holding something like the VAT rate on the
spreadsheet and accessing it via an absolute cell reference?
Q.11.3.6 Set up a spreadsheet that models the money you spend each week and what
you spend it on. The spreadsheet should have the days of the week down the side and
the things you spend your money on across the top. Provide totals for each day and for
each item you spend money on. Produce a print.
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Chapter 11 - Spreadsheets
R11 Optional Further Research
R.11.1 Using a spreadsheet it is easy to produce graphs. Find out how you do this with
the spreadsheet that you are using and produce a bar chart and a pie chart from one of
the spreadsheets you developed in this chapter.
R.11.2 Modify one of the spreadsheets that you have developed for the Manchester
United trip so that 10% is added to the money everybody has to pay. The 10% should
be held on the spreadsheet and referenced by absolute cell references. Change the 10%
to 12.5% and ensure the spreadsheet is updated correctly.
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Chapter 12 - Graphics
Chapter 12 - Graphics
12.1 Definitions for this Chapter
Graphic : A picture, graph or image that has been produced on a computer.
Bitmap : A picture that is built up from pixels.
Vector : A picture that is described in terms of points and how those points are joined
together.
12.2 Graphics
12.2.1 Introduction
Graphics are simply pictures on the computer and as a picture is worth a thousand
words they are an important part of Information Technology.
However just saying they are pictures on a computer does not really explain the
different types of graphics. Here are a few examples.
 The pictures used in a computer game.
 Pictures drawn by the computer based on some branch of mathematics. The most
famous example is probably fractals.
 Graphs and Charts that are used to help show how a business is performing. For
example, a graph could be produced which shows how sales have increased over
the past year.
 Architects use graphics to represent a building they are working on. This is often
called CAD (Computer Aided Design).
12.2.2 How graphics are stored
There are two main ways to store graphics on a computer; pixel based formats and
vector based formats.
If you look at a newspaper picture using a magnifying glass or microscope you will
see that the picture is actually made up of small dots. When viewed from far enough
away the dots create the picture. This is similar to a pixel based format on a computer.
The image is stored as a series of pixels (see chapter 6; especially 6.3.1) and the
computer just draws each of the pixels onto the screen to create the picture.
It is slightly more complicated than that as the number of colours has an affect on how
much space is needed to store each pixel. Also, many pixel based file formats
compress the data so that it does not take up so much disc space. But, the concept is
quite simple. Each pixel is held which, when displayed, creates a graphic.
Vector based graphics work differently. They describe the position of various points
that make up the picture and how those points are related. When the graphic is drawn
on the screen it uses this information to draw the various lines and points on the
screen.
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Chapter 12 - Graphics
Q.12.2 Questions
Q.12.2.1 If the same image is stored as a pixel based format and as a vector based
format, what format do you think would be most suitable to use if the image had to be
enlarged? Hint : Try drawing a circle on squared paper and then enlarging it by
making each pixel (square) bigger so that it occupies four squares instead of one.
R12 Optional Further Research
R.12.1 There are many different file formats available; for example GIFF, BMP,
JPEG, WMF etc. Find at least six different file format standards and find out in which
situations you would use them. Also say if they are pixel based or vector based.
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Chapter 13 - Communications and Networks
Chapter 13 - Communications and Networks
13.1 Definitions for this Chapter
Data Communication : Communication of data either between two computers or
between a computer and a person.
Telecommunications : Communicating data over long distances, usually over
telephone lines but could also be via satellite, micro waves etc.
Facsimile (Fax) : Using a telephone line to transmit documents.
Computer Network : Two or more computers that are connected together so they can
share data or devices such as printers or CD-ROM’s.
Local Area Network (LAN) : A relatively small network of computers. The computers
are usually in a single building such as an office or a school.
Wide Area Network (WAN) : A network of computers which connect computers over
a large area. The computers are often in different towns and even in different
countries.
Modem : A device which allows a computer to be connected to a telephone line.
Modem is short for MOdulator-DEModulator.
13.1 Introduction to Communications and Networks
We are all familiar with communication. We do it every day. Some forms of
communication are given here.
 Talking to people.
 Watching television.
 Listening to the radio.
 Reading books.
 Using a fax machine to transmit documents over telephone lines.
 Using a telephone.
 Using teletext to access information supplied by television companies.
Communication between computers is just another form of communication.
Every time you sit down at a computer you are taking part in a dialogue that is a form
of communication.
However a computer does not only communicate with people. A computer can also
communicate with other computers. Consider a Cash Card Machine. The machine into
which you insert your bank card is a small computer but it has to communicate with
another computer that holds your account details so that it can check you have enough
money in your account before it gives you any money.
In order for computers to communicate with one another they have to be connected
together. This is done by way of a network.
A network can be as simple as a piece of wire joining two computers together or it can
be a network that allows the computer to talk to millions of other computers all over
the world.
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Chapter 13 - Communications and Networks
Some benefits of having computers networked together are given below
 Computers can share information. It is easy for somebody to pass a copy of a file to
somebody else.
 There is only one source of data. The company can keep all their information on a
single computer and let everybody access that data.
 Devices such as printers and CD-ROM’s can be shared rather than every computer
having their own.
 Disc space requirements can be reduced as applications can be accessed from a
central point rather than everybody having their own copy.
 Maintenance is easier as support personnel can maintain the system via the
network.
Q.13.2 Questions
Q.13.2.1 One of the benefits of a computer network is that it allows everybody to
share a common source of data. Why do you think this is important?
13.3 Types of Network
There are two main types of network.
13.3.1 Local Area Network (LAN)
A Local Area Network (LAN) is a computer network that is located at one location;
typically an office or a school.
The computers are usually connected together by wires which run around the building.
There is normally somebody (or a team) who is responsible for the network and they
will ensure everybody can access the parts of the system they are entitled to access but
restrict access to the parts they are not authorised to use.
Often there are passwords that stops unauthorised people accessing the system.
13.3.2 Wide Area Network (WAN)
Wide Area Networks (WAN’s) connect computers together over large distances. It is
quite normal to join several LAN’s together via a WAN.
A LAN is normally connected via cables that have been run around the building. This
is obviously not convenient for WAN’s. Therefore other ways are used to connect
WAN’s together. Examples are;
 Fibre Optic Cables. These are supplied by third party companies and rented to
various users.
 Satellite and Micro Wave links.
 Telephone lines; either used by dialling up the computer you wish to communicate
with or by having a fixed line which is available all the time (often called a leased
line).
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Chapter 13 - Communications and Networks
It is worth noting that if you wish to communicate using the telephone line you need a
Modem (Modulator - Demodulator).
This equipment takes the data from the computer and converts it to a form that is
suitable for the telephone network. When the data arrives at the receiving computer
another modem does a similar operation but this time converts it from the telephone
format to a format which the computer can understand.
Q.13.3 Questions
Q.13.3.1 Think of three business in your local High Street that you think would use a
LAN and three that are probably connected to a WAN.
Q.13.3.2 The sale of modems has increased in the past few years. They have been sold
to people who wish to access the biggest computer network in the world. What is this
network?
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Chapter 14 - Control Systems
Chapter 14 - Control Systems
14.1 Definitions for this Chapter
Control System : Everything that in needed is order to control a particular device. This
includes all the hardware and software.
Output Port : A point on a computer into which a device can be plugged so that the
processor can communicate with the device.
Input Port : A point on a computer into which a device can be plugged so that the
device can communicate with the processor.
Control Signal : A signal from a processor to a device which tells it what to do.
Interface : A piece of hardware or software that sits between a processor and a device
which allows them to communicate.
Converter : A type of interface that converts signals from one form to another so that
a
processor/device can communicate.
Sensor : A detector that monitors on behalf of a device so that signals can be sent to
the processor.
Feedback : The ability of a device to provide signals to the processor about its current
state.
LOGO : A computer programming language.
Turtle : An electronic turtle or a turtle represented on the computer screen that is
controlled by LOGO.
Procedure : A series of instructions in a programming language that are grouped
together and can be executed by a single instruction.
14.2 What is a Control System?
A control system is a combination of everything that is needed to control a certain
device. This may involve a computer, some software, some additional hardware and
the device being controlled.
A good example is a robot. The computer will be running software that tells the robot
what to do. There will be some additional hardware that connects the computer and
the robot together. The device being controlled is the robot itself, whether just a
robotic arm or something that can move around, see things and pick things up.
However it is not only external devices that are control systems. A disc drive inside a
computer is an example of a control system.
The processor sends data to the disc drive together with instructions as to what to do
and the disc drive acts upon those instructions and tells the processor when it has
finished.
There are examples of control systems scattered throughout your house. A washing
machine is just one example.
Q.14.2 Questions
Q.14.2.1 Give examples of three other control systems that you would find in your
home.
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Chapter 14 - Control Systems
14.3 Communicating with the devices
The computer (or micro-processor) has to have some way of communicating with the
device it is controlling. Connection from the computer to the device is made via an
output port. This is a point on the computer where you can plug in the device. The
computer you use at school will probably have at least two output ports where a
mouse and a printer are connected.
Control Signals are used to tell the device what to do. In the case of a (simplified) disc
drive there will be a control signal that says the data that follows should be written to
the disc and another signal that says the disc drive should retrieve some data from the
disc.
Control signals can take various forms. For example, it could be a change of voltage
on a wire or it may be signals sent by radio waves.
In some circumstances there may have to be a converter between the computer and the
device. This is needed if the pieces of equipment use different signals. For example,
the computer may use digital signals and the device may use analogue signals (see
Chapter 1; especially 1.2).
In this case a Digital-to-Analogue (D-A) Converter is needed to convert digital signals
to analogue signals. Similarly an Analogue-to-Digital (A-D) converter will be needed
to convert signals being sent from the device to the computer.
An A-D (or D-A) converter is an example of a special type of interface that is needed
in order to allow the two pieces of equipment to work together.
An interface may be needed for other reasons. For example, if the two pieces of
equipment operate at different speeds an interface may be needed in order to keep the
two pieces of equipment in sync.
Q.14.3 Questions
Q.14.3.1 Do you think there is a need for any sort of interface between a mouse the
processor?
14.4 What can the computer control?
Typically a computer can control the following types of devices.
A relay switch : A relay is a switch which can be on or off. If the computer was
controlling a device such as an electrical socket or a motor, then a relay would be
appropriate.
An actuator : When an actuator receives a signal it converts it into movement. Disc
drives use actuators to position the read/write heads to the required track. It is
important that the actuator moves the read/write head the same distance for each
pulse of electricity it receives.
A motor : An actuator could be used to turn a motor on and off. But a special type of
motor, called a stepper motor has to keep receiving signals in order for it to keep
going. Every time it receives a signal it moves the motor a small amount. Actuators
and stepper motors are closely related.
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Chapter 14 - Control Systems
Q.14.4 Questions
Q.14.4.1 For a motor which can be turned on and off how many control signals are
required?
14.5 Feedback
It is possible that the processor just sends signals to a device and that is the end of the
matter. But it is more common to have some sort of feedback so that the device can
inform the processor about various situations.
For example, a printer can tell the processor it is out of paper so that the processor can
stop sending information.
In order to be able to receive signals from a device the computer must have an input
port. This is the same as an output port but allows the computer to receive signals.
There also has to be some form of sensor so that the device can detect what is going
on. In the case of something like a burglar alarm the sensor will be something that can
detect movement.
An extension of this idea is to have a device which continuously collects data. The
data can be stored on the computer for later analysis or can be analysed as the data is
collected so that instant decisions can be made.
Q.14.5 Questions
Q.14.5.1 Give three examples of control systems that have some form of feedback
capability.
Q.14.5.2 Think of a system where a device that continuously collects data would be
appropriate.
14.6 Turtles and LOGO
Your school may have access to a computer language such as LOGO. This language is
used to control a turtle.
The turtle can either be a real one (or at least an electronic version of one) or a
representation of one that appears on the computer screen.
You control the turtle with simple instructions (control signals).
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Chapter 14 - Control Systems
14.6.1 Example of LOGO
Assuming the turtle is facing North, the following LOGO program will produce a
square:
No.
Program 1
LOGO Instruction
Effect
1
2
3
4
5
6
7
8
9
10
PEN DOWN
FORWARD 60
RIGHT 90
FORWARD 60
RIGHT 90
FORWARD 60
RIGHT 90
FORWARD 60
RIGHT 90
PEN UP
Puts pen down so any movements draw a line
Moves the turtle forward 60 steps
Turns the turtle 90 degrees
Moves the turtle forward 60 steps
Turns the turtle 90 degrees
Moves the turtle forward 60 steps
Turns the turtle 90 degrees
Moves the turtle forward 60 steps
Turns the turtle 90 degrees
Lifts up the pen
You may notice that the above program uses the same four instructions four times
(FORWARD and RIGHT). We can use the REPEAT statement to replace instructions
2 to 9; like this:
REPEAT 4 [FORWARD 60 RIGHT 90]
This is saying, repeat the instructions in brackets four times.
A further enhancement we could make is to make the instructions for drawing a
square into a procedure. This means grouping the instructions together and giving
them a name. Now if we want to draw a square we simply use the instruction:
SQUARE (or whatever
we named the procedure).
Q.14.6 Questions
Q.14.6.1 If you have access to LOGO run the program 1 from this section. If you do
not have LOGO then run the program ‘manually’ (that is, use paper and pencil). Hand
in the results.
Q.14.6.2 Using the LOGO language write a program that would draw a triangle that
has equal sized sides and equal sized angles (that is, an equilateral triangle).
Q.14.6.3 What do you think are the main advantages of writing procedures?
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Chapter 14 - Control Systems
R14 Optional Further Research
R.14.1 If you are interested in programming you might like to look at languages such
as BASIC, PASCAL, C or C++. These languages are used within industry and an
understanding of them could be important if you wish to take up a career in the
computer industry.
R.14.2 If you live near an industrial area you might like to arrange a visit to a
manufacturing plant that uses computers on, say, a production line. You might like to
produce a small project showing how the computers work, what type of control
signals are used and if there is any data logging.
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Chapter 15 - Developing Systems
Chapter 15 - Developing Systems
15.1 Definitions for this Chapter
System Life Cycle : The steps that are followed when developing and maintaining an
IT system.
Systems Analyst : The person who analyses the current system (if there is one),
produces the requirements for the new system and comes up with a design that will
meet those requirements.
Programmer : The person who writes the programs that have been specified by the
systems analyst.
Top-down design : The process of breaking tasks down into smaller and smaller tasks
until they are easy enough to understand and write programs for.
15.2 The System Life Cycle
The system life cycle represents the various stages that an IT system goes through,
from the moment it is a twinkle in somebody’s eye to the moment it ceases to be of
any use.
The system life cycle is very important as it provides a framework which is used to
control the development and maintenance of a system and this is very important.
Many systems, in large organisations, take hundreds of man years to develop and are
very expensive. An investment of this size needs a lot of control to ensure the project
is progressing satisfactorily and that the company is getting a good return on their
investment.
The system life cycle looks like this
New Requirement
Feasibility Study
Maintain
Analysis
Implement
Design
Build
Each of the following parts of the system life cycle is explained below.
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Chapter 15 - Developing Systems
15.2.1 New Requirement
The starting point for any IT system is that somebody has a requirement. It might be to
ensure a warehouse never runs out of goods, make sure the customers pay the correct
amount for their gas or to install a new set of traffic lights to make the traffic flow
better at a certain crossroads.
At this stage it is important to state exactly what the problem is. For example, is it to
get customers to pay their gas bills on time or is it to make sure they are charged the
correct amount ? (It will probably be both of these (and more) but you can see there
are two different problems).
15.2.2 Feasibility Study
This is a report that says whether the system is feasible or not. It may include some of
the following points (and probably more). Some of these points may be discussed in
greater detail later in the system life cycle.
 Is the system cost effective? How much will the system cost to develop and will the
company get a return on the investment it plans to make?
 How long will the system take to develop? If it will take five years can the
company wait that long?
 Will the system be developed by the company’s staff or will an outside company be
asked to develop it? Alternatively are there any packages available that can be
bought that will do the job?
 Is the system practical to be implemented as an IT system? For example, if one of
the requirements is to be able to communicate with the system via speech is this
possible given the current state of technology?
 How will the company be affected by implementing the system? Will some of the
employees have to be made redundant? Will new employees be needed because of
the new system?
 What sort of training will be required; both to develop the system and to allow the
company’s employees to use it?
On production of the feasibility study the requirements of the proposed system might
change or it may even be decided to abandon the project altogether.
15.2.3 Analysis
The analysis phase allows the systems analyst (IT people who have the necessary
skills to analyse a current system and produce a specification for an IT system) to
investigate the system.
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Chapter 15 - Developing Systems
The systems analyst will do the following:
 Look at the current system (whether manual or already an IT system) to see what it
does and how it does it. This can be done by reading any documentation available
and by observing how the current system operates.
 Interview the people who use the current system to find out all they can about the
system and what their involvement is with it.
 Interview potential users of the new system to find out what their expectations are.
 Work out exactly what the new system has to do.
 Work out what other systems (whether computer based or manual) which the new
system has to communicate with.
At the analysis stage of the system life cycle no decisions are made as to which
hardware and software will be used (although in practise it is often assumed due to
hardware and software already being used by the company).
15.2.4 Design
The design phase takes all the work that the systems analyst has done and decides how
the system should be implemented. Actions carried out at this stage of the system life
cycle include:
 Deciding on the hardware and software to be used.
 Designing the screens that the user will see. This will also involve deciding on
what type of user interface will be used (e.g. command line or graphical).
 Deciding how data will be stored (e.g. on a database), what data is required and the
data type for each data item.
 Deciding what programs are required and what each program will do.
 Produce a specification that will allow computer programmers to actually write the
programs that will make up the system.
In carrying out the design the usual method is to use something called top-down
design (sometimes called stepwise refinement).
Using this method you start with the top level of the system (e.g. produce gas bills)
and gradually break this task down into smaller and smaller units until a task is easy to
understand and produce a program for.
15.2.5 Build the system
This stage is all about writing the programs and testing the system.
Initially a programmer will write the programs that have been specified by the systems
analyst during the design stage. The programmer will test the programs to ensure they
work as specified.
Once the program is working it will be tested with all the other programs that have
been written for the system. This is called System Testing.
The final stage of testing is called Acceptance System. This is when the future users of
the system test it to ensure it meets their requirements.
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Also, as part of the new system built, the necessary documentation will be prepared.
This will include manuals for the users as well as documentation that allows the
system to be more easily maintained. In fact a lot of the system documentation will
come from earlier stages of the system life cycle.
15.2.6 Implement
Once the system has been acceptance tested, the system is implemented. This phase of
the system life cycle might include the following:
 Loading live data onto the system. This might including keying in data held on
manual records, collecting data by some other means (e.g. scanning bar codes) or
converting the data from an existing system.
 Training the users how to use the new system.
 Moving all the programs to a secure area so that they cannot be tampered with.
 The system might be implemented for all the company in one go (sometimes called
the ‘big bang’ approach) or it might be phased in over a number of weeks or a
number of months (often called a phased implementation).
15.2.7 Maintain
The ‘maintain’ phase of the system life cycle is really the starting point to enter the
cycle again. Somebody will come up with a change that needs to be made to the
system. It might be a legal change (e.g. gas for the over 60’s has to be charged at a
special rate) or it might be a change in the company’s policy (e.g. high gas users get a
special discount).
Once the change has been identified the cycle moves into feasibility study and so the
cycle continues.
When carrying out your coursework project you will need to use elements of the
system life cycle.
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Chapter 16 - Documentation
Chapter 16 - Documentation
16.1 Definitions for this Chapter
Documentation : A means of communicating information about an IT system.
Typically the documentation is supplied as a manual but it is often supplied on CD
ROM.
Flowchart : A form of documentation that graphically represents a process.
16.2 Types of documentation
In the previous chapter we briefly mentioned documentation when building a system.
During the build stage of the system life cycle it is usual to produce a user manual and
a systems manual.
16.2.1 User Manuals
The user manual is the documentation that describes how to use the system. It should
describe what to do when the users want to achieve a particular result. As an example,
take a look at the manual for the word processor you have been using and see if you
can find out how to centre text on the screen. This is an example of something you
want to do so the user manual should tell you how to do it.
The user manual should also tell you what to do if you get an error message (what
does it mean and what do you do to recover from it). It may also tell you how to install
the software.
16.2.2 System Manuals
System Manuals are used by those people who have to maintain the system. The
manual describes the system so that future developers can refer to it when deciding
what changes have to be made.
System manuals are typically split into a number of levels. The top level will describe
the whole system (often on a single page). It will say where the system fits into the
organisation and what other systems it communicates with.
The bottom level of the system manuals will describe each program so that a
programmer does not have to look at a program listing and work out what it is trying
to do.
16.3 Flowcharts
When producing documentation a wide variety of techniques can be used. One
technique, called flowcharts, is often used when describing processes.
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Chapter 16 - Documentation
A flowchart uses symbols to represent certain operations. Here are some examples
Disc File
Magnetic Tape
General Operation
Decision
An example of using a flowchart to describe a typical process is as follows.
Writing and Posting a Letter
Write Letter
Buy Stamp
No
Got a stamp?
Yes
Stick stamp on
envelope
Post Letter
This is obviously a trivial example but it demonstrates how processes are represented
and how decisions are catered for.
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Chapter 16 - Documentation
This example shows how file updates are represented.
Accept pupil name
from keyboard
Print Error
Message
Validate name
No
Name Okay?
Yes
Student Database
Add name to database
Again, this is only a simple example but notice how the student database is updated
only after a valid name has been input.
Also note that some of the operation boxes have a double line at the top. This shows
that this is a high level task that has another flowchart somewhere else which further
explains how that particular process works.
This is an example of stepwise refinement.
Q.16.3 Questions
Q.16.3.1 Draw a flowchart of the processes involved in making a cup of tea
Q.16.3.2 Draw a flowchart which expands the ‘Validate Name’ Box. Your flowchart
should check that both a first name and a surname has been entered and that neither
exceed 20 characters in length.
R16 Optional Further Research
R.16.1 Decide upon a computer program that you wish to write. Before starting to
write the program plan it using a flowchart. Try to keep each flowchart to one page
and use sub-flowcharts where necessary.
Only when you have finished flowcharting process should you write the program
using a language of your choice. Once the program is complete ensure the flowchart is
updated so that it accurately represents the program.
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Chapter 17 - The impact of IT
Chapter 17 - The impact of IT
17.1 Definitions for this Chapter
Electronic Funds Transfer (EFT) : Moving money from one bank account to another
using data communications between computers.
Electronic Data Interchange (EDI) : Moving data from one computer to another,
primarily to carry out a business transaction without the need for paper.
17.2 A brief History
IT has already had a big effect on our lives; arguably a bigger effect than the Industrial
Revolution.
It may come as a surprise that IT (using computers) is relatively young. The first
working computer was not produced until the 1940’s, with computers not being sold
until the fifties.
By the 1960’s many large companies had computers and used them for tasks such as
payroll and stock control. These computers filled rooms the size of football pitches
and they had to be air conditioned due to the amount of heat they generated.
To communicate with these computers you normally had to be in the same room and it
was usually by means of a teletype terminal.
In the 1970’s computers were getting smaller and mini and micro computers were
introduced. In addition the visual display unit become a lot more common.
In this decade the banks started using MICR to speed up cheque clearance.
The 1980’s were a boom time for computers. Personal computers became common
place. DOS and Windows (and Microsoft) almost dominated the PC business.
The Graphical User Interface (GUI) became the accepted way to communicate with
PC’s.
The range of software also increased and, as computers became more powerful, the
type of work they could do also increased.
By the ‘80’s most people would have used a computer (even if they were unaware of
it). Washing machines, video recorders, card cash machines and many other devices
used a computer of some description.
The cashless society, although not with us by the 80’s, looked increasingly more likely
as we got used to using Credit and Debit cards.
Most medium to large businesses had (and relied) on computers.
If the 1980’s saw the rise of the PC, then the 1990’s look like being the decade of
communication. The Information Superhighway (the Internet, Cyberspace - call it
what you will) has touched many lives and it is now possible to communicate with
millions of other computers and people for the price of a local phone call.
Computers are also becoming ever more powerful and it is possible, with a multimedia PC, to play video and sound.
Many small businesses have computers and many homes have a PC somewhere in
their house.
Most children use computers at school and are growing up computer literate.
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Chapter 17 - The impact of IT
17.3 The effect IT has had on our lives
Here are just a few ways that IT have affected our lives:
 We are now a more cashless society. We can pay by credit and debit cards.
Electronic Funds Transfer (EFT) is also widespread. EFT allows money to be
moved from one bank account to another using data communication between
computers. The majority of people are paid via EFT.
 More business is conducted using Electronic Data Interchange (EDI). EDI allows
goods and services to be sold without the need for paper forms. For example, you
can buy insurance via EDI. You go into an insurance broker and select the policy
you want. Your order will go directly to the insurance company and update their
database without the need to send any forms.
 The majority of office workers have a PC on their desk. This allows them to access
a lot more information than they could do before and also makes them more
effective in their day to day tasks.
 More personal data about us is held on computers. This helps companies in many
ways. One example, is that they can offer us products through the post which we
know we have an interest in.
 The government of the day holds information about us on computers. This can
speed up things like payment of Social Security and also help detect fraud. Some
people argue it is an invasion of privacy that the government (and companies) hold
all this information.
 Many homes in the country have a PC in their house. This helps students carry out
their school work, can help in areas such as the household accounts and can be
used for entertainment; such as playing games.
 Using on-line services such as the Internet we can communicate with people all
over the world. It is also possible to shop through these services.
 Many people are made redundant due to IT being introduced into the workplace. A
counter argument is that many IT related jobs are also created so overall it balances
out.
 IT is allowing many people to work from home (tele-work). This means less
commuting saving both time and money. But some of the reason for going to work
is for the social interaction that takes place.
Q.17.3 Questions
Q.17.3.1 Consider the statements given in 17.3 above. Choose three. Give a different
justification to those already given as to why it is a good thing and also give an
opposite viewpoint. Finally, state which viewpoint you agree with.
Q.17.3.2 Give another three areas where IT has changed our lives. State whether you
think they are a good or bad thing and give your reasons.
Q.17.3.3 Many jobs are lost through the introduction of IT into the workplace. Give
three reasons why this happens.
Q.17.3.4 The Data Protection Act was introduced in 1984. What are the main aims of
this act (you need to research this question).
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Chapter 18 - Your Coursework Project
Chapter 18 - Your Coursework Project
18.1 Introduction
As well as sitting an examination you will also have to produce some coursework
which will count towards your overall mark.
The coursework is very important. It accounts for 60% of the total mark and should be
taken seriously.
Before you start your coursework try to do the following:
 Make sure you know what is required. It is not just about showing that you can use
a computer. Typically you will have to show that you have used IT to solve a
problem.
 Try to look at projects from previous years. This will give you some idea of what
is required.
 Once you have decided on your project try to write down the main objective in one
or two sentences. If you cannot do this you will gradually get more and more
confused about what you are trying to achieve as the project continues.
 If you can, take a look at the marking scheme. As the project progresses, make
sure that you are addressing the areas where marks are awarded. For example, if
you create a database it may be pointless entering a thousand records if you can
enter just ten records and still pick up full marks for showing that you have
developed a system that meets the objectives you set out at the start of the project.
18.2 What shall I do for my coursework?
One of the biggest choices you have to make (assuming it is not made for you) is what
your coursework will be about. You will probably want to look for a problem that you
can use IT to solve. Here is a small list of suggestions but make sure you choose to do
something that interests you otherwise you will lose interest half way through.
 Putting the accounts of a small business onto a spreadsheet.
 Cataloguing your CD, Record and Tape collection on a database.
 Keeping a list of all your friends. You could include who you exchange birthday
(and Christmas) cards with, when you last sent them a letter, when you last spoke
to them on the phone.
 Managing a knock out competition for a local sports club.
 Managing the membership details of a local club. This could include sending out
letters when membership is due for renewal and keeping track of all the accounts.
18.3 How do I do my coursework?
In undertaking your coursework you need to adopt a logical approach. The following
is a list of steps you might go through. It is important that you document each stage as
these reports can form part of the overall project documentation.
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Chapter 18 - Your Coursework Project
18.3.1 Propose the Project
This document will describe to your teacher the problem you are trying to solve. You
should include the people who are affected by the project and what benefits they will
see once the project has been implemented.
Your teacher will have to agree with your project proposal before you are allowed to
continue.
18.3.2 Analysis
This stage of the project will be a more detailed analysis of the problem. You need to:
 Interview the people involved to find out exactly what they want.
 State exactly what the proposed system will do.
 Define all the data the system will be storing and where and how you will collect
it.
 Define what output will be produced by the system.
At this stage of the project you do not say how you will solve the problem. You are
simply stating what the problem is and what you need to do in order to solve the
problem.
18.3.3 Design the System
This is the stage where you say how you will solve the problem. You can investigate
potential solutions, evaluate packages and consider what hardware you need.
Depending on the project you may have to:
 Design programs (e.g. produce flowcharts).
 Define the structure of a database (e.g. say what fields you will use and assign a
data type to each one).
 Plan how a spreadsheet will be developed (e.g. what the rows and columns will
represent).
 Plan out how a letter will look (e.g. the wording of a letter to the member of a
club).
You may also have to do some work on designing forms for data capture, defining
exactly how the output will look and deciding how you will check the data has been
entered accurately.
18.3.4 Implement the System
During this part of the project you will actually build the system that you have been
planning. This might include writing computer programs, setting up a database or
spreadsheet or creating various letters and forms on a word processor.
It is important that you test the system. This should be done in a logical way. One way
of doing this is to decide what input data you will use and then work out what output
it will produce. When you enter the planned input you can check to see that you get
the expected output.
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Chapter 18 - Your Coursework Project
It is important to test every part of the system. Try putting invalid values into the
system to see that the system rejects them. Also try putting values that are on the
borders of the allowed values. For example, if you write a program that allows the
user to input a number between 1 and 100, try putting in 99, 100 and 101.
Whilst testing, keep a copy of your results as this can be used in your project
documentation.
18.3.5 Document the System
If you have been documenting the system as you go along you should have much of
the documentation already prepared.
You may need to finalise the system documentation and also produce a user manual so
that other people can use the system.
18.3.6 Evaluate the System
It is important that you produce a report which evaluates your project.
 Did you meet the original objectives you set yourself?
 What problems did you have and what did you do to resolve them?
 What could you do to further improve the system?
 What would you do different if you did the same project again?
 Was the project a success? If not, why not?
The evaluation ties up all the loose ends of a project and makes sure that you learnt
from it. It can also be a good starting point for other people considering a similar
project as they can see what problems you had and how you would resolve them if you
did it again.
You may have noticed that the method suggested above is very similar to the system
life cycle (see Chapter 15). You do not have to follow the system life cycle or the
procedure outlined above but it is important that you have some plan as to how you
will tackle the project.
Not only will you be able to check that you are progressing at a suitable pace but it can
also give you a framework into which you write your coursework report.
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Chapter 99 - Answers to Questions
Chapter 99 - Answers to Questions
Q.12 Questions
Q.1.2.1 Give three examples of IT, that you use every day.
A.1.2.1 There are obviously many answers. Examples are watches, faxes, mobile phones, radios,
televisions, washing machines.
Q.1.2.2 Looking at the five main areas of IT, above, give one example of each area that you use in
everyday life.
A.1.2.2 The students can give many examples. Possibilities are:
Handling Information : Searching an address book for a friends address.
Communicating Data : Phoning up a friend.
Measuring and Control : Using a TV remote control.
Presenting Information : Writing a school essay.
Modelling the Real World : Keeping a school timetable that models your day.
Q.1.3 Questions
Q.1.3.1
Would you consider the following digital or analogue?
i The music coming from a speaker. (analogue)
ii The price of postage stamps. (digital)
iii Whether a bank account is in credit or debit (in the black or in the red)? (digital)
iv The different combinations of colours a traffic light can have. (digital)
Q.1.3.2 Give an example of something which is digital and something which is analogue?
A.1.3.2 There are many answers. Digital examples include, stations on a TV set and a digital watch.
Analogue examples include tuning an old fashioned radio and a clock with hands.
Q.2.2 Questions
Q.2.2.1 Give two examples of information?
A.2.2.1 Almost any answer will do as long as it has meaning to somebody.
Q.2.2.2 Give two examples of data?
A.2.2.2 Almost any answer will do as long as it can be justified as being data.
Q.2.2.3 Whether something is information or data sometimes depends on who is looking at it. Give two
examples where this could be the case and say who would regard it as information and who would
regard it as data?
A.2.2.3 Many answers are acceptable. Two examples are
 A personal diary written in a code would be information to its owner but only data to anybody else.
 A news bulletin in English would be information to English speaking people but data to everybody
else.
Q.2.3 Questions
Q.2.3.1 Look at the following data and say which data type best describes it.
i
12 (integer)
ii
a (character)
iii
aa (string)
iv
-34.98 (numeric)
v
A telephone number (string - probably not numeric as there are likely to be spaces and
you will not want to perform numeric operations on the data)
vi
Your age (integer)
vii
Your Christian Name (string)
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Chapter 99 - Answers to Questions
Q.2.4 Questions
Q.2.4.1 What characters do you think make up the character set of the English language?
A.2.4.1 All the letters (upper and lower case), all the digits and all the punctuation symbols. These
should definitely be included. The student may include others.
Q.2.4.2 What is the character set for all the non-vowel characters in the English alphabet.
A.2.4.2 B through to Z excluding A, E, I, O and U. The student may also include the lower case set as
well as the digits and punctuation characters.
Q.2.5 Questions
Q.2.5.1 Give three examples of where you use codes in your daily life, almost without realising it.
A.2.5.1 Almost any sensible answers are acceptable. For example, postcodes, CD ( for CD-ROM),
£3.20 (for three pounds and twenty pence) and a Telephone STD code to represent an exchange.
Q.2.5.2 If you were asked to introduce a coding scheme for the Premier Division Football teams how
would you do it? As well as devising a coding scheme what else would you need to think about?
A.2.5.2 There are ten teams in the Premier league so a one character code would be enough. But it
might be more sensible to code the teams as two characters so that teams like Liverpool and Leeds
(which both start with ‘L’) can use their second letter to identify them.
Alternatively, you might use a three character code which fits in with some of the normal football
conventions (e.g. QPR for Queens Park Rangers).
You need to think about what to do if there is still a clash after the first two (or three characters ). For
example, ‘Manchester City’ and ‘Manchester United’.
You also need to be aware there that the codes will change as teams are promoted and demoted.
Q.2.6 Questions
Q.2.6.1 Consider a class register. Identify what happens to it during the various phases of the data
processing life cycle.
A.2.6.1 Data Collection : Who is attending that class?
Data Input : Write the names in the register.
Data Processing : Mark attendances and absences.
Output : Produce a report on attendance for the Headmaster.
Q.3.2 Questions
Q.3.2.1 If some data is in RAM why should you regularly copy the data to a disc drive?
A.3.2.2 Because data is lost from RAM when the computer is turned off (or if there is a power cut) and
unless you copy it to a disc you will lose the data.
Q.3.2.2 What is one advantage of distributing software (programs) on CD-ROM as opposed to using
floppy discs?
A.3.2.2 Possible answers include:
 It is cheaper as a CD-ROM costs less to post than a number of floppy discs.
 It is easier to install the software as you do not have to keep swapping floppy discs.
 You can run programs from CD-ROM so you do not have to use space on your hard disc - this is not
usually true of floppy discs.
 The software providers normally give ‘extras’ away as they have spare space on a CD-ROM.
Q.3.2.3 From the following list decide if each item is hardware or software?
i
A Floppy Disc (Hardware)
ii
A Word Processing Program (Software)
iii
A Computer Game (Software)
iv
A Joystick (Hardware)
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Chapter 99 - Answers to Questions
Q.3.3 Questions
Q.3.3.1 What do you think is a disadvantage of a multi-user system?
A.3.3.1 Possible answers include:
 If too many people are using the system the response time could be slow.
 If there is a problem with the system all the users are affected (how do you feel when you can’t get
money out of a cash machine due to ‘computer error’ ?)
Q.3.3.2 What do you think is a disadvantage of a single-user system?
A.3.3.2 Possible answers include:
 You may not have access to corporate data, which is somewhere else - possibly on the mainframe.
 Your computer may not be powerful enough to run the software you need in order to do a certain
job.
Q.3.4 Questions
Q.3.4.1
Do you think the following are interactive or real time processes or both?
i A flight simulator (both)
ii Using a calculator (interactive)
iii Booking a holiday at a travel agents (both)
iv A crossword puzzle on a computer (interactive)
Q.3.4.2 When you buy a train ticket you can reserve a seat. Do you think the train operator could use
a single user system to provide this service? If not, why not?
A.3.4.2 No. The bookings have to be done on a central, multi-user system so that the same seat is not
booked twice.
Q.4.2 Questions
Q.4.2.1 Collect five examples of forms that are designed to capture data. Say what you think are the
good and bad points about each form. Design your own form to collect data about your classmates.
How does your form compare to others in your class?
A.4.2.1 This is simply a matter of personal taste (although there are recognised good and bad practises
used in industry). For example, some students might think it good that boxes are provided for each letter
of your name. Others might see this as a restriction on the amount of data that can be input.
Q.4.2.2 Give three examples of data capture forms where the form has already been pre-printed with
details about yourself.
A.4.2.2 There are many examples including gas and electric meter reading forms, TV licenses, Road
Tax reminders, Mail Order Shopping orders.
Q.4.2.3 Design a simple questionnaire and try it out on people at school (both students and teachers).
What problems did you encounter? What could you have done to reduce these problems?
A.4.2.3 There are obviously many answers to this questions and many lessons to be learnt. It is almost a
mini-project and includes many other subjects as well as Information Technology.
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Q.4.3 Questions
Q.4.3.1 Next time you are in your local town see how many different ways you can find that retailers
capture data.
A.4.3.1 There are many answers including bar codes (and scanning), entering prices into tills, collecting
customer requirements on a form, giving an estimate/quotation and approaching customers to ask if they
can help.
Q.4.3.2 Apart from cheque and cash cards where else would you find a magnetic strip?
A.4.3.2 There are many answers including entry cards, London Underground tickets, Credit Cards and
Phone Cards.
Q.4.3.3 As long as you are aged sixteen or over you can go into thousands of shops, pay one pound and
see OMR in action. What would you be doing?
A.4.3.3 Entering The National Lottery.
Q.4.3.4 Give one advantage and disadvantage of OMR, OCR and MICR.
A.4.3.4 There are numerous answers. A sample answer (with two answers in each section) is given
below:
Advantages (OMR)
 1) It is a quick way to collect data. 2) It is less error prone than some other methods.
Disadvantages (OMR)
 1) The design of the forms can be complicated. 2) The person filling in the form has to follow the
instructions precisely.
Advantages (OCR)
 1) It saves time as the data does not have to be re-type. 2) It can understand hand-written and typed
characters.
Disadvantages (OCR)
 1) There can be a high failure rate in recognition. 2) Characters can be recognised incorrectly.
Advantages (MICR)
 1) It is difficult to forge. 2) It is a common standard within the financial sector.
Disadvantages (MICR)
 1) The system only recognises one set of characters (font). 2) MICR systems are expensive.
Q.4.3.5 Can you think of another type of input device that is commonly used to play games?
A.4.3.5 A joystick.
Q.5.2 Questions
Q.5.2.1 What do you consider are the main advantages of a GUI over a Command Line Interface?
A.5.2.1 There are many answers but you might expect to see these (or variations):
 It is easier to use (more intuitive).
 You do not have to remember long strings of commands.
Q.5.2.2 If you have access to an IBM compatible PC go to the Command Line Interface (the DOS
Prompt) and try these commands. What do they do?
i DIR (show all the files in the current directory)
ii CLS (Clears the screen)
iii COPY C:\AUTOEXEC.BAT MYFILE.BAT (Copies a file)
iv PROMPT $T (changes the prompt to the current time)
(Note : You may not be allowed access to the DOS prompt. In which case you will be unable to do this
question)
Q.5.2.3 GUI’s are sometimes called WIMP environments. Why do you think this is?
A.5.2.3 WIMP is an acronym for Windows, Icons, Menus and Pointer
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Q.6.2 Questions
Q.6.2.1 Give examples of two output devices - one which produces information and one which
produces data. Do not use examples given in the text and do not use computer output devices.
A.6.2.1 There are many answers. Two acceptable answers, in each category, are Personal Stereo
(information), TV Remote Control (data), Printing Press (information) and a Telephone when dialling a
number (data).
Q.6.3 Questions
Q.6.3.1 Teletext is an example of a screen mode. Would you say that a teletext display needs a high,
medium or low resolution monitor? Explain your answer.
A.6.3.1 Low. The characters are built from ‘chunky’ characters. There is no fine detail and no graphics
to talk of. Having said that they achieve some good effects.
Q.6.4 Questions
Q.6.4.1 Imagine you are a 24 pin dot matrix printer. Using graph paper show how you would print an
‘m’, an ‘a’ and an ‘!’.
A.6.4.1 You should receive a grid which is 24 units high. An ‘m’, ‘a’ and ‘!’ should be represented by
filling in the relevant squares. If the students use a magnifying glass they will be able to see the
individual dots on a page printed with a dot matrix printer.
Q.6.4.2 A printer can either be considered a character printer (where one character is printed at a time),
a line printer (where a complete line is printed at a time) or a page printer (where a whole page is
printed at a time). Classify a dot matrix printer, an ink jet printer and a laser printer into each of these
categories.
A.6.4.2 Dot matrix printer (character - typically), Ink jet printer (character - typically), Laser (Page).
Note : Line printers are normally connected to mainframes where a complete line is printed before the
paper is advanced.
Q.6.4.3 Many printers have two modes of operation; draft quality and letter quality (sometimes called
Near Letter Quality or NLQ). After reading the definitions at the beginning of this chapter how do you
think the two modes might be implemented on a dot matrix printer and a laser printer?
A.6.4.3 Dot matrix implementation is done by ‘missing’ dots.
Laser implementation is done by a printer with not such a high resolution (i.e. less dots per inch).
Q.7.2 Questions
Q.7.2.1 How many characters can you store on a 3.5” High Density Floppy Disc? How does this differ
from a 3.5” Double Density disc? (Note : this question requires research by the student).
A.7.2.1 3.5” HD = 1.4 million, 3.5” DD = 750,000 (both approx.)
Q 7.2.2 Using your knowledge of storage devices what do you think is the best medium for the
following types of data?
i. A large application distributed to a great many people (CD-ROM)
ii. An Operating System (ROM or Hard Disc)
iii. A weekly security copy (Magnetic Tape)
iv. A copy of a file that you need to take home (Floppy Disc)
v. A letter that you are writing to your friend (Hard Disc or RAM)
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Chapter 99 - Answers to Questions
Q.7.4 Questions
Q.7.4.1 Would you consider a CD-ROM a direct access or a serial device?
A.7.4.1 It is a direct access device but some data may have to be read serially. However it is important
that the students recognise it is predominantly a direct access device.
Q.7.4.2 Give one advantage of a direct access device and one disadvantage
A.7.4.2 It allows fast access to any piece of data. There is an overhead to allow this type of access.
Q.7.4.3 Give an example where direct access would be more suitable over serial access.
A.7.4.3 There are many examples. One possibility is a library. If somebody borrows a book you would
want direct access to the data about that book. If you had to read information about every book the
system would be too slow.
Q.7.5 Questions
Q.7.5.1 The directory structure shown in 7.5.2 can be represented as a tree structure. Draw a tree that
represents this structure.
A.7.5.1 The start of the tree is shown here:
C:\
accounts
gk
acroread
hk
Q.7.6 Questions
Q.7.6.1 Why is it important for a security copy of a file to be stored away from the computer which has
the original file on?
A.7.6.1 If there is a disaster such as a fire you need to ensure the security copies remain intact.
Q.7.6.2 Can you think of a disadvantage of compressing data as you take the security copy?
A.7.6.2 You have to expand the data before you can use it. This takes times and means you have to
have access to the program that does the expansion. For example PKZIP (to compress) and PKUNZIP
(to expand).
Q.8.2 Questions
Q.8.2.1 Is RAM hardware or software?
A.8.2.1 The electronic chips that make up the RAM are hardware. It can, at any point in time, hold
software; along with the data that is being processed.
Q.8.3 Questions
Q.8.3.1 What do you consider are the advantages and disadvantages of a custom designed package as
opposed to buying a package ‘off the shelf’?
A.8.3.1 Advantages
Does exactly the job you require.
Disadvantages
More Expensive.
It will need supporting.
You need to develop and maintain it (e.g. legal requirements).
Potentially long time to develop.
Q.8.4 Questions
Q.8.4.1 If you had to write an essay what would you look for in a Word Processing Package to assist
you.
A.8.4.1 This is largely a matter of personal opinion but typically the students might say they need a
spell checker, something to check their grammar and a Word Processor that can help with the
presentation of their finished document.
Q.8.5 Questions
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Q.8.5.1 What package would you use for each of the following tasks.
i.
Writing a report (Word Processor)
ii. Preparing company accounts (Spreadsheet)
iii. Keeping information about the products a company supplies (Database)
iv. Keeping a class register (Database - but Word Processing or Spreadsheets could also be
argued)
Q.8.5.2 Give an example of a use for each of the applications describe above. Say why the application
is suitable.
A.8.5.2 There are an infinite number of answers to this questions. The important point is that the student
can justify the answer.
Q.9.2 Questions
Q.9.2.1 Using any Word Processor you have access to, write at least three paragraphs, with each
paragraph occupying at least three lines. Make use of bold, italics and underlining. Also use different
fonts and sizes. Print the document.
A.9.2.1 A document should be presented that meets the specification set out in the question.
Q.9.2.2 Type the word ‘windws’ (windows without the ‘o’) into a Word Processor. Spell check it. What
suggestions are you offered as a replacement?
A.9.2.2 The actual list will depend of the Word Processor and the dictionary being used. The list might
include windows, winnow, wind, winds and windy.
Q.9.4 Questions
Q.9.4.1 Using the document you created in Q.9.2.1 change it so that the right and left hand margins are
1cm less than they were originally. Also change the paragraphs so that the first lines are indented by a
further 2cm. Print the document.
A.9.4.1 A document should be presented that you can check by inspection against the document handed
in for Q.9.2.1.
Q.9.6 Questions
Q.9.6.1 Using the document you created in Q.9.4.1 move the third paragraph so that it becomes the
second paragraph. Print the document.
A.9.6.1 A document should be presented that you can check by inspection against the document handed
in for Q.9.4.1.
Q.10.2 Questions
Q.10.2.1 What is the key field in a telephone directory?
A.10.2.1 The phone number. Everybody has a different phone number (compared to surname).
Q.10.2.2 For a school register say what is the datafile, the records, the fields and which field is the key
field?
A.10.2.2 Datafile = The register itself. Records = Students name and/or number and if they have
attended. Fields = Name and a series of repeating fields which represent a term (or week). Key Field =
Students Name and/or number. Other answers are possible.
Q.10.2.3 Give three examples of when it would be sensible to use a computerised database?
A.10.2.3 There are many possibilities including; an address book, a Christmas card list, a list of
birthdays, as well as the uses to which a company would use a database (e.g. stock control).
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Q.10.3 Questions
Q.10.3.1 If your school identified its classes by cathedrals (e.g. Salisbury, Canterbury etc.) what
change(s) would need to be made to the database definition shown above (section 10.3.1)?
A.10.3.1 The Class Number description should be changed (to Class Name?) and its data type changed
to Text(20).
Q.10.3.2 Create a computer database that holds data about everybody in your class. Decide for yourself
what data you want to keep. Next collect that data in whatever way you feel is appropriate, set up the
database using appropriate data types and then enter the data you have collected.
Produce a print of the database records and also a print showing the database structure. Also hand in
your data collection documents.
A.10.3.2 You should receive two prints and the data collection documents. These should show the
students understanding of how to set up and input data into the database.
Q.10.4 Questions
Q.10.4.1 Using the sample database we have developed in this chapter what expression would you use
to search for anybody in class 18 or for anybody with a surname of ‘Jones’?
A.10.4.1 Class Number = 18 OR Surname = ‘Jones’
Q.10.4.2 Using the database you created in Q.10.3.2 sort the data on one of the fields, carry out a query
and produce a print which does not show all the fields. Hand in three prints showing the results. Also
provide a brief description of the field you sorted on and the query you did.
A.10.4.2 You should receive three prints and an explanation of what the student was trying to achieve.
You can check the results against the previous database print.
Q.11.2 Questions
Q.11.2.1 Think of three situations which are models of the real world. Where does the model differ
from the situation it is modelling?
A.11.2.1 This is a very open question. One possible answer is a name and address book. It models the
people you know. It differs in many respects; for example it does not model their height, eye colour etc.
Q.11.3 Questions
Q.11.3.1 Look at the Old Trafford spreadsheet in 11.3.2 above and answer the following questions.
 What value is in cell C4?
 In what cell is the value ‘Paid so far’?
A.11.3.1 23.58, C2
Q.11.3.2 Using a spreadsheet package of your choice set up the Old Trafford spreadsheet as shown in
11.3.2. Try to match the formatting as closely as possible. Hand in a print of the result.
A.11.3.2 You should receive a print that matches the spreadsheet shown in 11.3.2 (as closely as the
package allows).
Q.11.3.3 Using the spreadsheet you produced in Q.11.3.2 answer these questions.
 Enter some text into cell B2. What happens and why?
 Increase the font size of ‘Amount to Pay’ by at least four points. What happens and what can you do
to correct it?
 Change the format of the cells which display numeric values so that a pound sign is automatically
displayed (e.g. entering 52.34 is displayed as £52.34). Why is it important not to enter the pound
sign when typing in the figures?
A.11.3.3 Part of ‘School visit to Old Trafford Football Ground’ disappears as it can no longer ‘flow’
into cell B2.
The cell is no longer big enough to accommodate the data. The cell width will have to be increased.
It treats the data in the cell as text.
Q.11.3.4 Using the spreadsheet you have been developing, use the SUM function to show how much all
the students have paid so far and how much is still outstanding. Produce a print.
A.11.3.4 The spreadsheet should have the following figures in the following cells; C6 = 62.99, D6 =
132.01. You might want to check that formulae have been used to generate these figures.
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Q.11.3.5 What is the benefit of holding something like the VAT rate on the spreadsheet and accessing it
via an absolute cell reference?
A.11.3.5 If the VAT rate changes you only have to change one cell on your spreadsheet and all the
other figures are automatically recalculated.
Q.11.3.6 Set up a spreadsheet that models the money you spend each week and what you spend it on.
The spreadsheet should have the days of the week down the side and the things you spend your money
on across the top. Provide totals for each day and for each item you spend money on. Produce a print.
A.11.3.6 A spreadsheet should be produced which meets the criteria of the question. The SUM function
should be used to work out the totals.
Q.12.2 Questions
Q.12.2.1 If the same image is stored as a pixel based format and as a vector based format what format
do you think would be most suitable to use if the image had to be enlarged? Hint : Try drawing a circle
on squared paper and then enlarging it by making each pixel (square) bigger so that it occupies four
squares instead of one.
A.12.2.1 Vector based graphics are better for scaling as pixel based graphics tend to become ‘jagged’
when enlarged.
Q.13.2 Questions
Q.13.2.1 One of the benefits of a computer network is that it allows everybody share a common source
of data. Why do you think this is important?
A.13.2.1 It means there is no duplication of effort in entering and maintaining the data. It also means
there is not inconsistency in the data caused by people holding their own files.
Q.13.3 Questions
Q.13.3.1 Think of three businesses in your local High Street that you think would use a LAN and three
that are probably connected to a WAN.
A.13.3.1 There are many answers but the best test that can be applied is if the company is part of a
national/multi-national company. Then they are likely to be connected to a WAN (e.g. Banks, Building
Societies, Insurance Companies, Travel Agents etc.)
Companies likely to have a LAN are medium sized self-contained businesses that have a number of
computers (e.g. solicitors, estate agents, accountants etc.)
Q.13.3.2 The sale of modems have increased in the past few years. They have been sold to people who
wish to access the biggest computer network in the world. What is this network?
A.13.3.2 The Internet.
Q.14.2 Questions
Q.14.2.1 Give examples of three other control systems that you would find in your home.
A.14.2.1 Possible answers include Video Recorder, CD Player, TV Remote control, an automatic
camera and a video camera.
Q.14.3 Questions
Q.14.3.1 Do you think there is a need for any sort of interface between a mouse the processor?
A.14.3.1 Yes. A mouse is an analogue device. Therefore there is a need for an interface.
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Q.14.4 Questions
Q.14.4.1 For a motor which can be turned on and off how many control signals are required?
A.14.4.1 One or two. There could be two with one being for on and one for off. However one signal
could be used with the current state of the motor being reversed each time.
Q.14.5 Questions
Q.14.5.1 Give three examples of control systems that have some form of feedback capability.
A.14.5.1 There are many answers including a computer mouse (tells the processor when it is moving), a
burglar alarm (tells the processor when it detects movement), a telephone (tells the processor when
somebody is pressing buttons to dial a number) and a central heating system (tells the processor the
current temperature).
Q.14.5.2 Think of a system where a device that continuously collects data would be appropriate.
A.14.5.2 There are many answers. One possible answer is recording temperatures and wind speeds at
regular intervals for a weather forecasting system.
Q.14.6 Questions
Q.14.6.1 If you have access to LOGO run the program 1 from this section. If you do not have LOGO
then run the program ‘manually’ (that is, use paper and pencil). Hand in the results.
A.14.6.1 You should receive a square which is 60 ‘units’ in size.
Q.14.6.2 Using the LOGO language write a program that would draw a triangle that has equal sized
sides and equal sized angles (that is, an equilateral triangle).
A.14.6.2 One correct program would be:
PEN DOWN
REPEAT 3 [FORWARD 30 RIGHT 120]
PEN UP
(The repeat statement could consist of three separate statements)
Q.14.6.3 What do you think are the main advantages of writing procedures?
A.14.6.3 You do not have to replicate instructions in different parts of the program. This makes it easier
to read, easier to maintain and more reliable as the procedure should be fully tested before it is used
within a program.
Q.16.3 Questions
Q.16.3.1 Draw a flowchart of the processes involved in making a cup of tea.
A.16.3.1 There are many answers. You should check that the main elements of making tea are present
(add milk, add sugar, pour tea, fill kettle etc.) You should also check that there are relevant decisions
e.g. Do you take sugar? Do you take milk? Has the kettle boiled?
Q.16.3.2 Draw a flowchart which expands the ‘Validate Name’ Box. Your flowchart should check that
both a first name and a surname has been entered and that neither exceed 20 characters in length.
A.16.3.2 The flowchart will be different for each pupil but they should have common features. They
should all have decision boxes checking that the first name and surname has been entered. They should
also have decision boxes that check that neither part of the name exceeds 20 characters in length.
The flowchart should NOT get the name from the keyboard. This is done on the higher level flowchart
and including it in this would mean the user being asked twice.
Q.17.3 Questions
Q.17.3.1 Consider the statements given in 17.3 above. Choose three. Give a different justification to
those already given as to why it is a good thing and also give an opposite viewpoint. Finally, state which
viewpoint you agree with.
A.17.3.1 The answers the students give are almost immaterial as long as they provide some sort of
justification.
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Q.17.3.2 Give another three areas where IT has changed our lives. State whether you think they are a
good or bad thing and give your reasons.
A.17.3.2 Again, the answers are almost immaterial. The aim of these questions is to make the students
consider the implications of IT and not just consider the positive viewpoints.
Q.17.3.3 Many jobs are lost through the introduction of IT into the workplace. Give three reasons why
this happens.
A.17.3.3 There are many answers. Some samples are:
 People are more efficient now that many companies use an electronic office so less secretaries and
clerical staff are needed.
 Companies who automate their manufacturing process do not need as many people to produce the
same amount of goods.
 Companies which do not keep up with the IT revolution face stiffer competition and may go
bankrupt as they cannot compete.
 Companies such as railway operators and telephone operators rely on computers to monitor their
operations and do not need as many people.
 Industries such as printing have been deeply affected by the IT revolution. The industry has changed
almost beyond recognition and require a lot less people.
Q.17.3.4 The Data Protection Act was introduced in 1984. What are the main aims of this act (you need
to research this question).
A.17.3.4 There are eight main principles to this act.
1. The information to be held shall be obtained and processed fairly and lawfully.
2. Personal data shall be held only for one or more specified and lawful purposes.
3. Personal data held for any purpose shall not be used or disclosed in a manner incompatible with that
purpose.
4. Personal data shall be adequate, relevant and not excessive in relation to the purpose for which it is
being held.
5. Personal data shall be accurate and kept up to date.
6. Personal data shall not be held for longer than is necessary.
7. An individual shall be entitled, without undue delay or expense, to view the data being held about
them and, where appropriate, have it amended or deleted.
8. Appropriate security measures should be taken to protect the data.
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