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CHAPTER #1
INTRODUCTION TO COMPUTER
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WHAT IS DATA?

DATA

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Data is a plural word and its singular form is datum
‘Datum’ is a Latin word meaning “something given”
Numbers, characters, symbols, images etc., which can be
processed by computer
Data is a collection of facts made up of text, numbers and
dates:
Murray
35000
7/18/86
Any raw collection of facts and figures which is not
meaningful to the user is called data
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TYPES OF DATA
 There are three types of data to be entered
in the computer:
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Alphabetic Data:
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Capital letters from A-Z, and small letters from a-z.
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Numeric Data:
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Decimal numbers from 0-9, decimal point notations.
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Alphanumeric Data:
Alphabetic, numeric and special characters/symbols.
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WHAT IS INFORMATION?

INFORMATION
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Processed or meaningful form of data is called
information, like "Farhan, 40" are two data items,
but "Farhan is now 40 years old" is an information
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example
Mr. Murray is a sales person whose annual salary
i$35,000 and whose hire date is July 18, 1986
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WHAT IS A COMPUTER
 The word computer is derived from the word compute which
means to calculate something
 With this meaning a computer is considered to be a
calculating device that performs the arithmetic operations at
enormous speed
 Now-a-days computer is not just the calculating device but it
can perform many operations, so we can define as:
“Computer is an electronic device that processes data,
converting it into information that is useful to people”.
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Advantages and Disadvantages
of Using Computers
What are the advantages of using computers?
Speed
Reliability
Storage
Consistency
Communications
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WHAT ARE THE DISADVANTAGES OF
USING COMPUTERS?
Violation of
Privacy
Health Risks
Impact on
Labor Force
Impact on
Environment
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CHARACTERISTICS OF COMPUTER
SPEED
 A computer is a very fast device. It can perform in a few
seconds the amount of work that a human can do in a day
ACCURACY
 Every task is performed by computer with same
accuracy. Errors may occur in computer due to
human
DILIGENCE
 Human beings get bored from work on the same
thing for a long time and also tired. But the case is
not same with computers, a computer is free from
tiredness, lack of concentration
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Characteristics of Computer (Cont..)
VERSATILITY
 A computer is capable of performing almost any task. It just
requires the particular software to perform that task
POWER OF REMEMBERING
 A computer can store and recall even after several years
any amount of information because of its storage
capability
NO FEELINGS
 Computers are devoid of emotions. They have no feelings
I.Q
 A human think with their mind that what is right for them and what
is not. While a machine has no I.Q. But programmers are trying to
make computer an intelligent machine.
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INFORMATION TECHNOLOGY
 Information technology is the use of modern
technology to aid in storage, processing, analysis
and communication of information.
 We can simply define that the information about
any technology is called information technology.
 Information technology means the use of the
hardware, software, services, and supporting
infrastructure to manage and deliver information
using voice, data and video.
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BRIEF HISTORY OF COMPUTER
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Computers did not suddenly arrive.
The research on the computer technology is a process of
hundreds of years and is still in progress
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The latest computer is the result of several minds.
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The history of computer development is often referred to in
reference to the different generations of computing devices
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Each generation of computer is characterized by a major
technological development that fundamentally changed the
way computers operate
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Brief History of Computer (Cont..)

There are five generations of computers
1. First Generation (1940-1956)
2. Second Generation (1956-1963)
3. Third Generation (1964-1971)
4. Fourth Generation (1971-Present)
5. Fifth Generation (Present and Beyond)
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Brief History of Computer (Cont..)
1. First Generation (1940-1956)
 In this generation of computer vacuum tube was used for
circuitry
 These computers were very large in size, taking up entire
rooms
 They were very expensive to operate and in addition to using
a great deal of electricity, generated a lot of heat
 First generation computers relied on machine language
 The UNIVAC (Universal Automatic Computer) and ENIAC
(Electronic Numeric Integrated and Calculator) computers are
examples of first-generation computing devices
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Vacuum Tubes in First Generation
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ENIAC Computer
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UNIVAC Computer
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Brief History of Computer (Cont..)
2. Second Generation (1956-1963)
 Transistors replaced vacuum tubes in the second
generation of computers
 The transistor was invented by Bardeen in 1947 .
 Through the use of transistors the second generation
computers were much faster and more reliable than the
first generation of computers
 Second-generation computers moved from machine
language to symbolic, or assembly languages, which
allowed programmers to specify instructions in words
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TRANSISTORS
First Transistor
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IBM-7094 Computer
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Brief History of Computer (Cont..)
3. Third Generation (1964-1971)
 The development of the integrated circuit was the main
achievement of the third generation of computers
 An Integrated Circuit (IC) or a chip is a small electronic
device made out of a semiconductor material (transistor)
 The earliest ICs used a technology called SSI (Small
Scale Integration contain up to 100 transistors) and MSI
(Medium Scale Integration contain 100-3000 transistors)
 The third generation computers were smaller, more
efficient and more reliable than their predecessor were
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Integrated Circuit
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Brief History of Computer (Cont..)
4.
Fourth Generation (1971-Present)
 The microprocessor brought the fourth generation of
computers, as thousands of integrated circuits were built
onto a single silicon chip
 What in the first generation filled an entire room could
now fit in the palm of the hand
 LSI (large-scale integration): From 3,000 to 100,000
electronic components per chip
 During this the first microprocessor the Intel 4004 was
developed and was followed by VLSI (Very Large Scale
Integration contain 100,000 to 1,000,000)
 ULSI (ultra large-scale integration): More than 1 million
electronic components per chip
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First Microprocessor Intel 4004
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Fourth Generation First PC
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Brief History of Computer (Cont..)
5.
Fifth Generation (Present-Beyond)
 Fifth generation computing devices, based on artificial
intelligence, are still in development, though there are
some applications, such as voice recognition, that are
being used today, Expert System, Robots etc.
 The goal of fifth-generation computing is to develop
devices that respond to natural language input and are
capable of learning and self-organization
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 Intelligence
the ability to learn and understand.
 Artificial intelligence
is the branch of computer science.
It is the study how to make computer to do things more and more
better than human.
 Expert system
is an intelligent computer program which consists of some knowledge
about particular field, then using this knowledge ,it provide the
answer to those people who don’t have any access to the experts in
that particular field.
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TYPES OF COMPUTER
1.
2.
3.
4.
ACCORDING TO HARDWARE
ACCORDING TO PURPOSE
ACCORDING TO SIZE
ACCORDING TO USE
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 ACCORDING TO HARDWARE
1. ANALOG COMPUTER
2. DIGITAL COMPUTER
3. HYBRID COMPUTER
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Types of Computer (Cont..)
1. ANALOG COMPUTER
 Analog computer is used to process analog
data
 Analog data is a continuous and having an
infinite variety of values
 Such type of data include temperature,
pressure, speed, weight, voltage, depth etc.
 Examples of analog computer are
Speedometer of car, Thermometer etc.
 Analog computers are faster
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Types of Computer (Cont..)
2.
DIGITAL COMPUTER
 A digital computer as its name implies
works with digits to represent numerals,
letters or other special symbols
 A digital computer process digital data
 Digital data is a discrete data and having
only two possible values (0, 1)
 Digital computer provide accurate results
but they are slower than analog computer
 Analog computers lack memory whereas
digital computers store information
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Types of Computer (Cont..)
3. HYBRID COMPUTER
 A hybrid computer is a combination of
digital and analog computers and it
combines the best features of both types of
computers
 For example a petrol pump contains a
processor that converts fuel flow
measurement into quantity and price
 Hybrid computer is used in hospitals to
measure the heartbeat of the patient
 Hybrid Computers are also used in
scientific applications or in controlling
industrial processes
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2..Types of Computer (w.r.t. purpose)
1. GENERAL PURPOSE COMPUTER
• Most computers in use today are general purpose
computers
• These are built for a great variety of processing
jobs
1. SPECIAL PURPOSE COMPUTER
• A special computer as the name implies is
designed to perform a specific operation
• Special purpose computers are also known as
dedicated computers
• Such computers would be useful in games,
control traffic lights, weather prediction etc.
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3..TYPES OF COMPUTER (W.R.T. SIZE)
1.MAINFRAME COMPUTERS
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Mainframe computers are large in size, expensive
and more powerful system
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The largest mainframes can handle the processing
needs of thousands of users at any given moment
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Mainframe computers are used in large
organizations, such as insurance companies, banks,
universities, and international markets, where
many people need to use the same data
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 In a traditional mainframe environment, each user
accesses the mainframe’s resources through a device
called a terminal
 Examples of mainframe computers are IBM-4381,
ICL-2900, and NEC 610 etc.
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Mainframe Computers
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MINI-COMPUTER
First released in the 1960s, minicomputers got their
name because of their
small size compared to other computers of the day
The capabilities of a minicomputer are somewhere
between those of mainframes and personal computers.
For this reason, minicomputers are often called
midrange computers
Powerful Minicomputers can serve the input and output
needs of hundreds of users at a time
Users can access a central minicomputer through a
terminal or a standard PC
Examples of mini computers are PRIME-9755 and IBM
System 36 etc
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MINI COMPUTER
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3.SUPERCOMPUTERS
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Supercomputers are the most powerful computers made, and
physically they are some of the largest
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These systems can process huge amount of data, and the fastest
supercomputers can perform more than one trillion calculations
per second
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Supercomputers are ideal for handling large and highly complex
problems that require extreme calculating power
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Supercomputers are used for forecasting the weather, oil
exploration, film imagery, and modeling complex processes like
nuclear fission
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Examples of supercomputers are CRAY-1 and CYBER-20
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Super Computer
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 TYPES OF COMPUTERS ACCORDING TO USE
1.
INDIVIDUAL USE
2.
ORGANIZATIONAL USE
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1.INDIVIDUAL USE
 Most computers are meant to be used by only one person at a
time
 Such computers are often shared by several people, but only
one user can work with the machine at any given moment
 Such type of computers are examples of Personal Computers
(PCs)
 Personal Computers are also called microcomputers, because
they are among the smallest computers created for people to
use
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The six primary types of computers in this
category are:
1. >> Desktop Computers
2. >> Workstations
3. >> Notebook Computers
4. >> Tablet Computers
5. >> Handheld Computers
6. >> Smart Phones
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DESKTOP COMPUTERS
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The most common type of personal computer is the desktop
computer
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A PC that is designed to sit on a desk or table
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These computer not only enable people to do their jobs with greater
ease and efficiency, but they can be used to communicate, produce
music, edit photographs and videos, play sophisticated games, and
much more
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As its name implies, a desktop computer is a full-size computer that
is too big to be carried around
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The main component of a desktop PC is the system unit, which is
the case that houses the computer’s critical parts, such as its
processing and storage devices
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DESKTOP COMPUTERS
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There are two common designs for desktop
computers
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The more traditional desktop model features a
horizontally oriented system unit, which usually
lies flat on the top of the user’s desk
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Many users place their monitor on top of the
system unit
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DESKTOP COMPUTERS
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Vertically oriented tower models have become the
more popular style of desktop system
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The design allows the user to place the system unit
next to or under the desk
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WORKSTATIONS
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A workstation is a specialized, single user computer that typically has
more power and features than a standard desktop PC
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These machines are popular among scientists, engineers, and animators
who need a system with greater-than average speed and the power to
perform sophisticated tasks
Workstations often have
large, high resolution
monitors and accelerated
graphics handling
capabilities
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NOTEBOOK COMPUTERS
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Notebook computers, as their name implies, approximate the shape of
an 8.5-by-11 inch notebook and easily fit inside a briefcase
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Because people frequently set these devices on their lap, they are also
called laptop computers
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Notebooks are fully
functional microcomputers
and they are portable
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TABLET PCS
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The tablet PC is the newest development in portable, full-featured
computers
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Tablet PCs offer all the functionality of a notebook PC, but they are
lighter and can accept input from a special pen-called a stylus or a
digital pen-that is used to tap or write directly on the screen
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Many Tablet PCs also
have a built-in microphone
and special software that
accepts input from
the user’s voice
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HANDHELD PCS
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Handheld personal computers are computing devices small enough to
fit in your hand
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A popular type of handheld computer is the Personal Digital Assistant
(PDA)
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A PDA is no larger than a small appointment book and is normally
used for special applications, such as taking notes, displaying telephone
numbers and addresses
Many PDAs let the user access
the Internet through a wireless
connection, and several models
offer features such as cellular
telephone, and cameras etc.
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SMART PHONES
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Some phones offer advanced features not
typically found in cellular phones, they are
sometimes called smart phones
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These features can include Web and e-mail
access, special software such as personal
organizers, or special hardware such as digital
cameras
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2.COMPUTERS FOR ORGANIZATIONS
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Some computers handle the needs of many users at the
same time
These powerful systems are most often used by
organizations, such as businesses or schools, and are
commonly found at the heart of the organization’s network
The largest organizational computers support thousands of
individual users at the same time, from thousands of miles
away
These computer are:
Network Servers
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Mainframe Computers
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Minicomputers
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Supercomputers
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NETWORK SERVERS
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Most organizations’ networks are based on
personal computers
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Individual users have their own desktop
computers, which are connected to one or more
centralized computers, called network servers
A network server is usually a powerful personal
computer with special software and equipment that
enable it to function as the primary computer in the
network
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ELECTRONIC DATA PROCESSING
 Raw data is transformed into information by processing it
 Data Processing is a series of steps, actions or operations that converts data
into meaningful information, or input into output
 This can be accomplished by using machines, labor and procedures
 When the data entered in the computer is manipulated, formulated ,sorted
and passed through mathematical or statistical formulas, so it is known as
Electronic Data Processing
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FUNCTIONS OF ELECTRONIC DATA PROCESSING
 All data processing, whether done by hand or by the latest
computer system, consists of three basic activities:
• Capturing the input data
• Manipulating the data
• Managing the output results
Input
Processing
Output
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CONVENTIONAL DATA PROCESSING
 The conventional data processing system is the manual method
of transforming data into information
 The human beings themselves collect data, classify and
arrange according to the items of the data, perform manual
calculations and hence produce the required output result
 Because of this processing method, the system is also termed
as Manual Data Processing System
 Example is Type Writer machine
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ELEMENTS OF AN ELECTRONIC DATA PROCESSING SYSTEM
 There are four basic elements of an EDP system, these are:
• HARDWARE
The physical components of a computer is called hardware
• SOFTWARE
The term software refers to the computer programs, routines
and packages required to utilize and control the operation of
the computer
• PROCEDURE
Procedure is a set of pre-planned steps and policies which
the computer system adopts in order to perform a specific
task
• PERSONNEL
The individuals who work in an environment basically
related to computers are known as computer personnel
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