Year 9 Information Technology
Semester One 2011
Name : ________________
Theory Topic:
Software
Contents
SOFTWARE
3
INTERFACE DESIGN
CHARACTER-BASED USER INTERFACE OR COMMAND LINE INTERFACE
GRAPHICAL USER INTERFACE
EXERCISE 1
3
3
3
4
SYSTEM SOFTWARE
7
OPERATING SYSTEM
SCHEDULING HARDWARE OPERATIONS:
MEMORY MANAGEMENT:
CONTROLLING PERIPHERAL DEVICES:
FILE MANAGEMENT:
SYSTEM SETTINGS:
SECURITY
SINGLE TASK/MULTI-TASK
SINGLE USER/MULTI-USER
UTILITY SOFTWARE
EXERCISE 2
7
7
7
9
9
9
9
9
9
11
11
APPLICATION SOFTWARE
14
SOFTWARE PACKAGES
FREEWARE
SHAREWARE
OPEN SOURCE SOFTWARE
CUSTOM SOFTWARE
SYSTEM REQUIREMENTS
EXERCISE 3
14
14
14
15
15
15
17
REFERENCES
18
Year 9 Information Technology
Topic: Software
Software
Software is the detailed instructions used to direct the hardware to perform a
particular task. It controls the processing and movement of data within a computer
system. A computer needs software to tell it what to do and it needs hardware to
carry out the actual work. There are two main types of software known as system
software and application software.
Interface design
The user interface is the way the user interacts with the software. The function of the
user interface is to provide a means of communication between the user and the
computer. There are two common types of user interfaces: the character-based or
command line user interface (CLI) and the graphical user interface (GUI).
Character-based user interface or Command Line Interface
The character-based user interface or
command line interface requires the
user to give instructions using only
characters. The user types the
characters using a keyboard. The first
widely used operating system was the OS/360 system and it used a character-based
interface. The OS/360 system was developed in 1964 for all computers in IBM’s
System/360 family. MS-DOS (Microsoft disk operating system) uses a characterbased interface. It was very popular and became the industry standard for IBMcompatible computers in the 1980s
Character-based interfaces are still being used. UNIX (pronounced ‘you-nicks’) is a
multi-user operating system that was developed by AT&T Bell Laboratories. The
character-based UNIX interface is similar to MS-DOS although the commands are
different. It is still widely used on Internet servers.
Graphical user interface
The graphical user interface (GUI, pronounced
‘gooey’) allows the user to give instructions using a
mouse, and clicking on icons and menus. A GUI
provides an easy-to-use and consistent interface for a
range of applications. Microsoft Windows (or
Windows) is the most popular GUI.
Some of the main features of a GUI are:
Window—everything done on the computer appears within a rectangular
frame called a window. The user can open several windows at the same time
and work on different programs. Each window can be closed, resized, moved,
minimised or maximised.
Icon—a small picture that represents a program, file, folder or shortcut. Text
describing the icon appears when the user points at the icon. Double-clicking
the icon will open the file.
Menu—an onscreen list of available commands and tools. To open a menu,
click on the menu name. A pull-down menu will be displayed. A command is
then chosen by clicking on its name.
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Year 9 Information Technology
Topic: Software
Pointing Device to interact with the GUI.
So GUI’s are also known as WIMP environments – Windows, Icons, Menus, Pointing
device
Another variation of WIMP is Windows, Icons, Mouse, Pull-down menus.
GUI was first used by the Xerox Corporation in the 1970s. However, it was not until
the Apple Macintosh in 1984 that the GUI became popular. Microsoft followed a few
years later with the Windows OSBoth Mac OS and Windows have added new
features to their GUI to make them easier to use. Even though there are differences
many users can easily switch between operating systems.
GUIs offer several clear advantages over character-based user interfaces.
Applications developed for a GUI have the same consistent appearance as the
operating system. Skills learnt in one application can be used in another. For example
Cut, Copy and paste work similarly in all programs and are always found under the
Edit menu.
These features make it easier for people to understand and learn how to use a GUI
compared to a CLI. A GUIs are also more forgiving. Most dialog boxes have a
‘Cancel’ button and the ‘Undo’ command allows users to reverse the last action.
However, there are disadvantages with GUIs. They require faster processors, more
memory, more disk space, higher quality screens and the software is more complex
to write.
Features of a GUI
Application software written for a GUI must follow a strict set of guidelines that
control how the application looks and how standard operations are performed.
Exercise 1
1. Complete the following
a. What do GUI and CLi stand for.
b. Explain the difference between a GUI and a CLI.
c. What is it about a CLI that makes it harder to use than a GUI.
2. Describe the following GUI elements
a. Dialogue box
b. Window
c. Pull down menu
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Topic: Software
3. In relation to a Window what do the following mean
a. Title Bar
b. Minimise
c. Maximise
d. Close
4. What is a keyboard shortcut.
5. Complete the following table of keyboard shortcuts
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Year 9 Information Technology
Topic: Software
Operation
Mac OS X
Windows
Cut
Copy
Paste
Close window.
Print
Open
Save
Undo
Redo
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Year 9 Information Technology
Topic: Software
System software
System software manages all the operations needed to run the computer. It affects
the way the user interacts with a computer.
System software carries out a range of functions, such as
starting up the computer
loading the application software
storing files
communicating with peripheral devices
System software includes the operating system and utility software.
Operating system
The operating system (OS) is the software that supervises and controls the hardware.
It is usually installed on an internal hard disk of the computer.
Turning on a computer starts the boot process.
A ROM chip that contains the startup instructions (on older Intel
computers this was called BIOS (basic input output system), now called
EFI – Extensible Firmware Interface) executes a power-on self test
(POST) to make sure system hardware (system devices such as the video
display card, keyboard and mouse, hard disk) is connected and operating correctly.
After the POST is completed successfully, the BIOS/EFI loads the operating system.
The primary function of the startup program in ROM (BIOS/EFI) is to load and start
an operating system. The operating system runs continuously
whenever the computer is on.
Most of the time the operating system works in the background.
When you use an application it interacts with the operating system.
For example, to print a document you select the print command of
the application and a request is passed to the operating system,
which performs the task. The most common operating systems are
Windows, Macintosh, and different flavours of the Linux/UNIX operating system.
The operating system performs a variety of tasks:
Scheduling hardware operations:
The CPU or processor is required to perform many different tasks.
Older processors had only one core – the part that does the actual processing of
instructions – and could only do one task at a time. However, because the
processor is so fast it gave the appearance of performing many tasks at once.
Modern processors have multiple cores and so can do more than one task at a
time. Think of the processor as the brain and each core as an arm that can
perform a task. The operating system determines when the CPU will perform
each task. A common way of allocating CPU time is called time slicing. A time
slice is a fixed amount of CPU time. With this technique, each task in turn
receives a time slice. The operating system can also direct the CPU to switch
between different tasks to take advantage of idle time on one task.
Memory management:
The operating system controls how the CPU relates to
memory. It must ensure data is efficiently accessed and
not overwritten. This involves dividing the available
memory between different tasks and swapping data
between memory and secondary storage. Virtual
memory is a technique used by the operating system to
increase the amount of memory. It uses spare hard disk
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Topic: Software
space to supplement available RAM. Virtual memory is slower than RAM.
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Topic: Software
Controlling peripheral devices:
The operating system provides the communication with all input, output and
storage devices. It uses specific software for each type of peripheral device.
This specific software is referred to as a device driver or driver for short. For
example, a mouse driver is the software that tells the computer how to receive
data from a mouse.
Printers are relatively slow devices compared to other peripheral devices. To
increase printer efficiency the operating system uses a technique called
spooling. Spooling transfers the print job to a spool queue, where it waits until
the printer is free and it can be printed..
File management:
The operating system organises and keeps track of files. A file is a collection of
data that is recognised by a file name. It can be work you create on the
computer, a data file or an application. File names consist of unique names
followed by a period (.) and file name extension. The
file name extension indicates the type of information
stored in the file. Files are stored and organised into
folders (also called directories in some OS’s). A
folder can hold both files and additional folders. The
contents of a folder are displayed in a window. The
window shows the properties of the files and folders
of each file, such as the file name, size, type, or date
modified. Operations that can be performed are
create new files/folders, delete files/folders, open
files/folders, close files/folders, rename files/folders
and copy/move files/folders.
System settings:
The operating system allows the user to customize the many settings to the
user’s preference. For example, the System Preferences(Mac)/Control Panel
(Windows) allows you to change a computer’s theme, desktop background,
screen saver, screen resolution, time and netwok settings.
Security
Users can have individual usernames and passwords. The OS also tries to
protect users from themselves requiring passwords for some operations such
as deleting files and by requiring administrator level passwords to perform
operations such as installing/deleting software, adding/deleting user accounts.
There are various classifications of operating systems.
Single task/Multi-task
Single-tasking allows only one task to be performed at one time. Palm OS ,used
on a Palm handheld computer, is a single-task operating system. Personal
computers in the 70’s and 80’s were single task.
Multitasking allows several applications to work at the same time. Windows
and Mac OS are multitasking operating systems.
Single user/Multi-user
In addition to single and multitasking, operating systems are classified as
single-user and multi-user. A multi-user operating system allows many
different users to access the computer’s resources at the same time. UNIX is an
example of a multi-user operating system. Windows and Mac OS are single
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Year 9 Information Technology
Topic: Software
user operating systems.
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Year 9 Information Technology
Topic: Software
Utility software
Utility software performs routine tasks to support the operation of the computer
system. Operating systems contain utilities to assist in the management of the system.
However, users often purchase more powerful utility software. Some common
examples of utility software include:
 file compression to reduce the size of a file. It allows
the user to store more data and makes data
transmission faster.
 diagnostic tools to compile technical information
about a computer’s hardware and software
 disk scanners to detect and correct problems on a
disk and search for and remove unwanted files
 disk defragmenter to reorganise files and unused
space on a computer’s hard disk—allows data and
programs to be accessed faster
 uninstaller to remove an application and any
associated entries in the system files
 device drivers to provide communication with a peripheral device—
provided with the peripheral device or can be downloaded from the
Internet
 backup software to copy selected files or the entire hard drive onto
another disk
 anti-virus program to prevent, detect and remove viruses.
Exercise 2
1. Explain the difference between:
a. a file and a folder
b. single-tasking and multitasking
c. a disk scanner and a disk defragmenter.
2. Copy and complete the following sentences:
a. System software manages all the _______ needed to run the computer.
b. A _______ is a fixed amount of CPU time.
c. A file is a collection of data that is recognised by a _______.
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Topic: Software
d. _______ performs routine tasks to support the operation of the
computer system.
3. True or false?
a. BIOS/EFI executes a POST to make sure the hardware is connected
and operating correctly.
b. Spooling is the specific software for each type of peripheral device.
c. UNIX is an example of a single-user operating system.
d. Most operating systems do not contain utility software.
4.
a. What is an operating system?
b. List as many operations as you can that an OS can perform on files
and folders.
c. Apart from tasks on files and folders list four tasks performed by the
operating system.
d. How does the operating system manage memory?
e. List 10 custom settings available in Mac OS X.
f. Is Mac OS X or Windows 7 a single user or multi-user operating
system
g. List four utilities supplied with your computer.
h. Is there any type of utility that everyone should purchase? If so what
is it?
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Year 9 Information Technology
Topic: Software
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Topic: Software
Application software
Application software is a program used for a specific task. Application software
consists of off-the-shelf or software packages and custom software.
Software packages
An off-the-shelf software package is a complete and documented
program(s). Software packages can be bought to cover nearly all
requirements.
They include: word processing, desktop publishing, spreadsheets,
database management systems, paint programs, draw programs, web
browsers, video editing software, animation software, presentation
software, authoring software.
Software packages usually include documentation with instructions
for installing the software. Installing software transfers files to the hard
disk to enable the software to work. Most software packages contain
Quickstart guide, User manual and help files It is also common for
software companies to supplement and update their help files with
online help from their website. Access to this help often requires the
user to register their software package with the software company
Most software packages have new versions being developed. These
versions contain new features and hopefully any errors (or bugs) in the
previous version have been fixed (bug fix). The general version of a
software package is often recognised its title, such as Microsoft Office
2011 or Internet Explorer 7. The actual version is usually denoted as a
number. For example the current version of Word in the Microsoft
Office 2008 suite is Word 12.2.4
Major and minor changes to the software package are shown by a
change in the less significant numbers. Eg Word 12.3.1 is more up to date than Word
12.2.8
When you purchase a new version you are upgrading your application software. It is
important when upgrading or purchasing new software to check that your hardware
and operating system are compatible. The latest versions of the software often place
greater demands on the hardware and operating system. Upgrading your software
may require an upgrade in your hardware and operating system. Compatibility
requirements are usually specified on the software package and should be checked
before the application is bought.
Program suites contain several applications. The cost of an software suite is less than
the total price of each application. Examples of Program suites include MS Office and
Adobe CS.
Freeware
Freeware (from "free" and "software") is computer software that is
available for use at no cost or for an optional fee. Although users may
download it for no cost, the copyright owned by the author keeps the
software from being used in any way not expressly approved by its author.
Shareware
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Year 9 Information Technology
Topic: Software
The term shareware (also known as trialware or demoware) refers to proprietary
software that is provided to users without payment on a trial basis.
Shareware is usually offered either with certain features only available after the
license is purchased, or as a full version but for a limited trial period of time. Once
the trial period has passed the program may stop running until a license is
purchased. Shareware is often offered without supports or updates which only
become available with the purchase of a license. The words "free trial" or "trial
version" are also indicative of shareware.
Open Source software
Software available free of charge as an alternative to
conventional commercial models. Open source
software can be used and disseminated at will, and
the source code is open and can be changed as
required. The only condition is that the user make
such changes known and pass this information on to
others. Open source software is the shared
intellectual property of all developers and users and,
thanks to the collaboration, often achieves a higher level of quality than software
produced using conventional means.
Custom software
Even though software packages are very flexible one may not be available to do
exactly the task you need. Custom software is written for the needs of a specific
customer(s). It is written to fit the exact requirements of the problem and is labour
intensive. For these reasons custom software is expensive.
Custom software is written by a programmer using a programming language such as
C++ or Visual Basic.
System requirements
A computer system is made up of
hardware and software that work
together, processing data to achieve a
purpose. The relationship between
hardware and software is important.
Software depends on a particular
hardware configuration to work
effectively. This is known as the system
requirements for the software. Different
software places different requirements on the
hardware. For example a word processor
places less requirements on the speed of a
processor than movie authoring software.
All software companies are required to clearly
state the system requirements of their
products.
System requirements include
 Operating system
 Processor type and speed
 Amount of RAM
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Topic: Software
 Hard drive space
 Peripherals
The system requirements may also include specific peripheral devices. For example
movie authoring software would specify a DVD burner in order to create a DVD.
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Topic: Software
Exercise 3
1. True or false?
a. Microsoft Works is an example of a software package.
b. A software package is usually more expensive than custom software.
2. What am I?
a. Software that can be downloaded and used. A fee is paid only if you
decide to keep using it.
b. The process of transferring files to the hard disk to enable the software
to work.
c. Software that can be downloaded and used for no charge.
3. Copy and complete the following by replacing the letter in brackets with a
suitable term:
Users (a) their software when they purchase a new version. However, it is
important to check software and hardware (b) before purchasing the
software. The (c) versions of the software often place greater demands on the
(d).
4.
a.
b.
c.
d.
List the onscreen support provided by most software packages.
Why do users upgrade their software?
What is custom software?
List four things that are almost always specified in an applications
System requirements.
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Topic: Software
References
Grover, D. et al, (2007) Information and Software Technology
Powers, G. K. (2004) Information and Software Technology
Shelly, B.S. and Vermaat, M. E. (2010) Discovering Computers 2010: Living in a
Digital World, Introductory
Wilson, C. (2007) Exploring Information and Software Technology (4th ed)
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