INTRODUCTION TO COMPUTER AND
INTERNET
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Contents
Chapter 1:
Chapter 3:
1-Introduction to computer.
A-What is a computer ?
B- What computers do?
C-Computer system
D-Computer organization
E-Data, information and knowledge
F-Types of computers system
G-Generation of computers
3-Software:
A-System software.
B- Operating system.
C-Application software.
Chapter 2:
Chapter 6:
2-Hardware:
A-Input Devices.
B-Output Devices.
C- Processing Devices.
D-Storage Devices.
E-Other Devices.
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Chapter 4:
4-Network.
Chapter 5:
5-Internet.
6-Virus.
Chapter 7:
7-Numbers system:
A-Decimal Numbers.
B-Binary Numbers.
C-Octal Numbers.
D-Hexadecimal Numbers.
Chapter 1
INTRODUCTION TO COMPUTERS
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WHAT IS A COMPUTER?
*A computer is : a programmable
machine that receives input, stores
and manipulates data, and provides
output in a useful format.
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*A computer is a machine that
manipulates data according to a list
of instructions.
*A computer is an electronic device
that work according to instruction
given by programs.
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What computer do ?
1- receive input ( by input device (s)).
2- process information ( by processor
(CPU)).
3-produce output(by output device(s)).
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Computer Features
• store large amount of data and
information for a long period of time.
• process data and information in high
accuracy level.
• speed in processing data information.
• sharing of information /network.
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Computer system
Computer components
HARDWARE
SOFTWARE
USERS
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Computer system
The components of a computer system are :
:physical components
of your computer such as monitor
,cables , keyboard ,system unit , mouse
and printer.
 The hardware cannot do anything
without software.
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: A program consists of
The step-by-step instructions that tell the
computer what to do and how to do its
work .
Such as : word processing , operating
system , computer games.
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: a person who uses the
software on the computer to do
some tasks .
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A basic computer consists of three major components:
CPU (Central Processing Unit), IO (Input / Output) and
Memory .
Figure 1 : Computer organization
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Data comes through Input and the
CPU processes the data based on a
program which is in Memory.
The result is returned to Memory or is
presented to the user.
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What the difference between Data,
Information and knowledge ?
Data
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Computer
(Processing)
Information
Knowledge
*Data : is the name given to basic facts
such as names and numbers.
*Information : is data that has been
converted into a more useful or intelligible
form.
*Knowledge : arrangement of
information and classifying information
of the same type or the same topic.
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DATA:
Data is raw ,unprocessed facts , including text,
numbers , images and sounds.
Four common types of files are:
1- Document files ,created by word processors.
2-Worksheet files, created by electronic spreadsheets.
3-Database files, typically created by database
management programs.
4-Presentation files, created by presentation graphics
programs.
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TYPES OF COMPUTER SYSTEM
• There are four types of computers :
1-Microcomputers=personal computer =pc
2-Minicomputers
3-Mainframe Computers
4-Supercomputers
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Microcomputers
• A microcomputer is a computer with a
microprocessor as its central processing unit
(CPU).
• They are physically small compared to
mainframe and minicomputers.
• There are four types of microcomputers:
desktop, notebook, tablet PC and handheld
computers.
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* A desktop is intended to be used on a
single location.
* Notebook also known as laptop
computers.
* Tablet pc is type of notebook computer
that accepts your handwriting.
* Handheld computers are the smallest
and are designed to fit into the palm of
one hand.
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Minicomputers
* A minicomputer : is a class of multi-user
computers.
* Minicomputers are computers that are
somewhere in between a microcomputer and
a mainframe computer.
* is a multi-user computer that is less powerful
than a mainframe.
* is a multi-user computer capable of supporting
up to hundreds of users simultaneously.
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- More processing speed and storage
capacity then microcomputers.
- General data processing needs at small
companies.
- Larger companies use them for specific
purposes.
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Mainframe Computers
* Mainframes a powerful multi-user computer
capable of supporting many hundreds or
thousands of users simultaneously (at the
same time).
* Larger machines with special wiring and
environmental controls.
* Faster processing and greater storage then
minicomputers .
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* Typical machine in large organizations.
* They are used in Banks and Government
departments.
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Supercomputers
√ These systems are the largest, fastest and the
most expensive computers in the world.
√ An extremely fast computer that can perform
hundreds of millions of instructions per
second.
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- For example , NASA uses supercomputers to
track and control space explorations.
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GENERATION OF COMPUTERS
• A generation refers to the state of
improvement in the development of a
product.
• The development of computers is also gone
through phases of growth, which is called as
Computer Generations.
• Major technological developments in each
generation led to smaller, cheaper, more
powerful and more efficient computers.
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First Generation (1940 -1956)
- First Generation - Vacuum Tubes:
These computers used valves
leading to a huge size and cost.
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Advantage :– 1. First device to hold
memory.
2. Only electronic device.
Defects:–
1. Too bulky.(huge)
2. They were producing heat.
3. Maintenance Problem.
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Second Generation (1956 -1963)
- Second Generation - Transistors:
These computers used transistors
that were more efficient and cheaper
than valves.
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Advantage – Faster, Reliable(More
trusted), Size reduced
Defects:– Over heated quickly,
maintenance Problem
Storage: – Magnetic disk.
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Third Generation (1964 -1971)
* Third Generation– Integrated Circuits: These
computers used Integrated Circuits (IC).
* Storage – Floppies.
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Fourth Generation (1971 – Present)
Fourth Generation – Microprocessors: These
computers used microprocessors. With
the introduction of VSLI (Very Large Scale
Integration), thousands of transistors
could be placed on a single chip.
Microprocessor
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Advantage – Compact, Production cost,
Less power consumption.
Storage – CDs
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Fifth Generation (Present and Beyond)
Fifth Generation
Artificial Intelligence: The fifth
generation computer tries to
infuse intelligence into
computers. The development of
these computers is still in its
infancy, but some examples that
can be given are various speech
recognition systems and robots.
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Assignment
Draw a table to compare between
the four types of computers :
Microcomputers - Minicomputers Mainframe Computers –
Supercomputers.
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