Information Technology
Session One
Ama Pokuah Obeng
Information Technology Defined
• People always think that when you talk about IT or ICT it simply means using personal
computers. The term IT goes beyond that so let’s define the term IT. But before we will
define the term IT lets break the term into its components.
• WHAT IS INFORMATION?
• Information is defined as data (data is raw facts we input into a computer system) which
has been processed and gives meaning to the user. It means that information always
makes meaning to the user.
•
• WHAT IS TECHNOLOGY?
• Technology is the tools, ideals and methods that enable one to establish a
communication link between people.
• WHAT IS IT?
• Information Technology (IT) is simply a means of using
technology (tools, ideas and methods) to get and manipulate data
(information).
• WHAT IS ICT?
• Information and communication Technology (ICT) simply means
the process of using technology to establish a communication
link between people. The technology could be television, computer
mobile, etc.
•
INFORMATION PROCESSING
• In information processing there are five main stages that are
involved. These stages are:
• Input
• Process
• Output
• Storing information
• Distribution of information
• The information processes of a computer can be
diagrammatically represented as shown below:
INFORMATION PROCESSING STAGES
• Stage 1 – Receiving data
• The end user input or enters data from an input device like the keyboard. Data is
supposed to be fed into the computer before anything can be done to it so the
user uses any input device to send data into the computer. This stage is referred to
as the input stage.
• Stage 2- Process data
• After the data has been put into the computer the data is then converted into a
form that the computer can handle which is done by the Central Processing Unit
(CPU) which is found inside the system unit.
• And the process by which the computer converts the input data into a form (binary
form) that the computer can handle is called Decoding. This stage of information
processing cycle is the process stage.
• Stage 3- Display Results (Information)
• Afterwards the data is converted back to a form that a human being can
understand and interpret. This process of converting the processed data back
to a form human beings understand is called Encoding. Then the encoded
data (information) is sent to the output device (e.g. monitor, printer, speaker
etc) for the end user which can now be considered as information. This stage
is referred to as output stage.
• Stage 4- Storing Information
• The processed data is then stored by using any of the storage devices.
Example of storage devices are pen drives, CD, DVD, hard disk etc.
• Stage 5- Information dissemination
• The processed data (information) can then be disseminated to the various
appropriate places.
Terminologies
• Data – This is raw facts and figures that we input into a
computer.
• Information- It is a data which have been processed to a
meaningful form.
• Decode- To convert raw data into a form that computers
understand.
• Encode- To convert the decoded data into its natural form that
human beings understand.
IT TOOLS
• There are various devices in which one can think about. And those of
the devices that can be used to establish any communication link
between people are called IT tools. Therefore an IT tool can be
defined as any device that can be used to establish a communication
link. Examples of IT tools include Computers, mobile phone,
Television Vision, Radio set etc.
• Uses of IT Tools
• When you talk of IT tools there are so many fields that can be useful
but we would be much concerned on the uses of IT tools in the fields
such as education, social and economics.
Introduction To
Computers
Objectives Overview
Explain why
computer literacy is
vital to success in
today’s world
Define the term
computer, and
describe the
relationship between
data and information
Describe the five
components of a
computer
Discuss the
advantages and
disadvantages that
users experience
when working with
computers
Define the term
network, and identify
benefits of sharing
resources on a
network
Discuss the uses of
the Internet and
World Wide Web
Objectives Overview
Distinguish between
system software and
application software
Differentiate among
types, sizes, and
functions of computers in
each category
Explain how home users,
small office/home office
users, mobile users,
power users, and
enterprise users each
interact with computers
Describe the role of each
element in an information
system
Discuss how society uses
computers in education,
finance, government,
health care, science,
publishing, travel, and
manufacturing
12
A World of Computers
• Computers are everywhere
13
Computers are everywhere: at work, at
school, and at home.
People use all types and sizes of
computers for a variety of reasons.
Computers are useful: they help us write
letters, find information on the Internet,
and even create our own music CDs.
In the workplace, employees use
computers to create correspondence
such as e-mail messages, memos, and
letters; manage calendars; calculate
payroll; track inventory; and generate
invoices.
At school, teachers use computers to
assist with classroom instruction.
Students complete assignments and
conduct research.
Banks place ATMs (automated teller
machines) all over the world, so that
customers can deposit and withdraw
funds anywhere at anytime.
At the grocery store, a computer tracks
purchases, calculates the amount of
money due.
Vehicles include on-board navigation
systems that provide directions, call for
emergency services.
The 20th century brought us the dawn of
the digital information age and
unprecedented changes in information
technology.
As we begin the 21st century, computer
literacy is undoubtedly becoming a
prerequisite in whatever career you
choose.
Computer literacy, also known as digital
literacy , involves havinga current
knowledge and understanding of
computers and their uses.
Because the requirements that determine
computer literacy change as technology
changes, you must keep up with these
changes to remain computer literate.
Today it is easy for nearly everybody to
use a computer because:
• Microcomputers are common tools in
all areas of life.
• New forms of learning have developed.
• New ways to communicate
• Information systems (IS) is the study of complementary networks of
hardware and software that people and organizations use to collect,
filter, process, create, and distribute data.”
Discovering Computers 2012: Chapter 1
20
To be competent with computer
technology, you need to know the five
parts of an information system:
people, software, hardware, data,
telecommunication networks .
What Is a Computer?
• A computer is an electronic device, operating under
the control of instructions stored in its own memory
that can accept input (data), processes the data
according to specified rules, produces information
(output) that is useful to the recipient and stores the
results for future use.
Peoplemake decisions daily using all types
of information such as receipts, bank
statements, transcripts, production
processes, audit reports, student’s grade
report, etc. Information must have value to
be useful in decision making.
Information Processing Cycle
Figure: A computer processes data into
information.
The Components of a Computer
• A computer contains many electric, electronic, and mechanical
components known as hardware
Input Device
• Allows you to enter data and instructions into a computer
Output Device
• Hardware component that conveys information to one or more
people
System Unit
• Case that contains the electronic components of the computer
that are used to process data
Storage Device
• Records (writes) and/or retrieves (reads) items to and from
storage media
Communication
s Device
• Enables a computer to send and receive data, instructions, and
information to and from one or more computers or mobile
devices
26
The Components of a Computer
27
Advantages and Disadvantages
of Using Computers
Advantages of
Using Computers
Disadvantages of
Using Computers
Speed
Health Risks
Reliability
Violation of Privacy
Consistency
Public Safety
Storage
Impact on Labour Force
Communications
Impact on Environment
Categories of Computers
Personal computers
Servers
Mobile computers
and mobile
devices
Mainframes
Game consoles
Embedded computers
Supercomputers
Microcomputers
Personal Computers
• A personal computer can perform all of its input, processing, output, and
storage activities by itself
• Two popular architectures are the PC and the Apple
• Desktop computer
Figure: Microcomputer System
Mobile Computers and Mobile Devices
Mobile
Compute
r
Mobile
Device
Personal computer
you can carry from
place to place
Computing device
small enough to hold
in your hand
Examples include
notebook computers,
laptop computers,
netbooks, ultra-thins,
and Tablet PCs
Examples include
smart phones and
PDAs, e-book readers,
handheld computers,
portable media
players, and digital
cameras
Mobile Computers and Mobile Devices
Notebook computer
Tablet PC
Smart phones and
PDAs
E-book reader
Mobile Computers and Mobile Devices
Handheld computer
Portable media
player
Digital camera
Game Consoles
• A game console is a mobile
computing device designed for
single-player or multiplayer
video games
Minicomputers (Servers)
• A server controls access to the hardware,
software, and other resources on a network
• Provides a centralized storage area for programs, data,
and information
Mainframes
• A mainframe is a large, expensive,
powerful (not as supercomputers)
computer that can handle hundreds or
thousands of connected users
simultaneously.
• Mainframes process more than 83 percent
of transactions around the world
Supercomputers
• A supercomputer is the fastest, most powerful
computer
• Fastest supercomputers are capable of processing more
than one quadrillion instructions in a single second
• Applications requiring complex, sophisticated
mathematical calculations use supercomputers.
• Applications in medicine, aerospace, automotive design,
online banking, weather forecasting, nuclear energy
research, and petroleum exploration use supercomputers
Computer Applications in Society
Education
Finance
Government
Health Care
Computer Applications in Society
Science
Publishing
Travel
Manufacturing