Computer:
- Computer is an electronic data processing device, which accepts and store
data input, processes the data input and generates the output in a required
format. All physical parts of the computer that we can touch or feel are known
as hardware. Example keyboard, mouse, monitor etc. A group of program that a
computer uses to perform specific task is called software. Example Mozilla
Firefox, MS Paint etc.
Working system of a
computer.
Computer is an electronic
machine that converts data into information by performing various actions on
data.
For example, a computer
might perform a mathematical, operation on two numbers or the logical operation
such as comparing two numbers and then display the result. Such operation
performed by a computer is called Information processing cycle.
The information
processing cycle or the working of a computer has four steps, they are as
follows:
The computer accepts
input: -The process of entering data and program into the
computer system. An input device includes keyboard, mouse, scanner etc. Input
includes words and symbols in a document, number for calculation, instruction
for completing a process, picture and so on.
The computer stores
data: -The process of saving data and instruction
permanently is known as storage. Storage device includes Hard disk, Tapes,
CD/DVDs, pen drive, floppy disk etc.
The computer processing
the data: - The task of performing operation like
arithmetic and logical operation is called processing.
The computer produces
output: - The process of producing results from the data for
getting useful information. Output device includes printer, monitor, speaker
etc.
Characteristics
of computers: The
major characteristics of computer are
1.
High-speed: -Computer is a very high speed
electronic device. It can perform any calculation in a few milliseconds.
Computer can perform complex calculation at a high speed that human being may
not be able to do. The following terms are used to describe the speed of
computer.
|
Unit
of Time
|
Parts
of Second
|
|
Millisecond(Ms)
|
1/1000 of seconds
|
|
Microsecond(Us)
|
1/1000000 of seconds
|
|
Nanosecond(Ns)
|
1/1000000000 of
seconds
|
|
Picoseconds(Ps)
|
1/1000000000000 of
seconds
|
|
Femtosecond(Fs)
|
1/1000000000000000 of
seconds
|
|
Altosecond(As)
|
1/1000000000000000000
of seconds
|
2.
Accuracy: - Even though the computer has great
speed, computers are very accurate. Computer acts upon the data as per given
instruction and then gives the desired output. So accuracy means if the data,
instruction is correct and reliable then the output produced by the computer is
also correct and reliable. This is known as Garbage In Garbage Out (GIGO).
3.
Storage capacity: -The physical
space inside the computer where we can store huge amount of data is called
storage. Example Hard disk, CD-ROM, DVD-ROMs, magnetic tape etc.
The
storage capacity for a computer is measured in
|
Units
|
Meaning
|
|
0 or 1
|
1 Bit
|
|
4 Bits
|
1 Nibble
|
|
8 Bits
|
1 Byte
|
|
1024 bytes
|
1 Kilobyte (KB)
|
|
1024 Kilobytes
|
1 Megabyte (MB)
|
|
1024 Megabyte
|
1 Gigabyte (GB)
|
|
1024 Gigabyte
|
1 Terabyte (TB)
|
|
1024 Terabyte
|
1 Petabyte (PB)
|
|
1024
Petabyte
|
1 Exabyte (EB)
|
|
1024 Exabyte
|
1 Zetabyte (ZB)
|
|
1024 Zetabyte
|
1 Yottabyte (YB)
|
4.
Diligence: -A
computer is capable of performing the task continuously in the same speed for a
long time. The characteristic of computer makes it useful for repetitive job
like process control and quality control.
5.
Versatility: -Computers
are versatile machine. Computers are being used in different areas for
different propose like in office, home, banks etc. the capabilities of computer
to perform different task and has a wide range of areas depending upon
different program used in it known as versatility.
6.
Automatic: -
Computers are automatic machine because one started on a job they carry out the
job without any human intervention until it is finished.
7.
Reliability-A
computer is a reliable machine. Modern electronic components have long lives.
Computers are design to make maintenance easy.
Limitation
of computer: Limitation
of computers are as follows
1.
No self-Intelligence: - Computer can do
very complex and dangerous task which are impossible for human being. It works
according to the give instruction only. It does not have any intelligence of
its own.
2.
No thinking and Decision making power
(IQ): - It cannot take any decision of its own, it does only
those tasks which are already instructed to it in the form of program. It is we
to decide what we want to do and in what sequences.
3.
No feeling:
- A computer cannot feel anything as human. It does not have feelings or
emotion, taste, knowledge and experience.
This it does not get tired even after long hours of works.
4.
No learning power:
- Computer has no learning power. Once we give instruction to a computer how to
perform a task. It cannot perform the same task if we do not give it any
instruction for the next time.
Application
areas of computers
1.
Office: - Important work performed in office such
as preparation of letters, reports, copy of advertisement, publicity, contract,
forms, notes etc are efficiently performed by computer. Computer helps the user
ion preparing, storing and retrieving information.
2.
Desktop publishing system: -All
magazines, newspaper, books, comics are produced using computers. Software such
as word-processing is used for text typing, dia for drawing, figure etc.
3.
Data Analysis:
Software such as spreadsheet can be used to tabulate result, calculate number
of students, average marks. One can prepare product sales, profit, invest from
an organization. Computers are widely used for statistical data analysis.
4.
Computer Aided manufacturing (CAM):
Computer is used to control the production of certain engineering products,
chemical products etc. Example in a mechanical industry, designer used Auto CAD
for designing the machines and machine parts. CAM system is used to automate
the production such as quality control, measuring the size of the item during
production, measuring packaging the item after production and many more.
5.
Graphics:
Computers are being used to draw drawing, graphics and picture. Graphics
packages such as MS paint, Adobe Photoshop, Coral Draw etc. are used for two
and three dimension drawing.
6.
Database Management:
Computers are extensively used to store and retrieve information. File are now
stored in magnetic memory. There is no need of paper to store the information.
Database management system not only stores the information but also does data
analysis of information popular database management software are ORACLE,
Sybase, SQL, MS ACCESS etc.
7.
Project management:
A project management project used to plan, schedule and control man power,
material and other resource needed to complete the project in schedule time
period at a reasonable cost. Computer are used to plan, schedule and perform
the detail analysis of the work done, in case of project delay, computer helps
to increase the speed id time for completion.
8.
Communication:
Computers are extensively used in sending and receiving information. The
information transfer may take place either between two points or throughout a
computer network that connects a number of computers or workstations. Different
communication services such as Electronic mail (e-mail), teleconferencing or
video conferencing, internet phone, bulletin board system (BBS), chatting,
online banking, satellite communicant etc. are used for communication.
9.
Education: In
educational institutions, computers are used as a teaching aid, information
resource and research tools. When a computer is used as a teaching tool, it is
referred to as Computer Assisted instructions (CAI). Internet technology
provides several educational materials, online lectures and tutorials for
students.
10.
Health and Medical field:
Computer is widely used in hospital to help doctors in diagnosis, getting
information on patients, diseases, treatment, drugs etc. Computer in hospital
are used in different medical units such as ICU, ECG, operation theater, X-ray,
recovery room, pathology etc. They are also used in administration and in
keeping patient records.
11.
Reservation System:
Computers store all information in connection with tickets reservation such as
train /bus/aero plane number, station, distance, number of seats.
12.
Banking:
- Computer in banking are used for different purpose such as general
computations, transaction handling, record keeping, ledger maintenance, online
services, ATM etc.
13.
Military:
-The computers have played an increasingly
important role in the military, The computers in the military have been adapted
or designed to do a broad range of tasks, such as analyzing intelligence,
organizing prudent data for military leaders, geospatial analysis, controlling
smart weapons, or communications.
