Computer, computer characteristics, types of computer, its advantages and disadvantages

1. Introduction To
Computer
By:
Prabesh Shrestha

2. Introduction
¤ Its an electronic device which accepts
input, processes data, stores data,
and produces output
¤ Input refer to whatever is sent to a
Computer system
¤ Data refer to the symbols that
represent facts, objects, and ideas
¤ A computer processes data in a device
called the central processing unit
(CPU)

3. How Computer Works

4. Definition
• Computer can be defined as “An electronic
and electromechanical device”
• It intakes raw data, manipulates it and
gives accurate output in the form of
information.

5. Characteristics of Computer
Main characteristics of the computer can be
summarized as:
1. Speed: Computer is very fast and accurate
device. It can process millions and millions of
instructions within seconds.
2. Accuracy: Computer results are highly accurate.
3. Memory: Computers have a large amount of
memory to hold a very large amount of data or
information.

6. 4. Diligence: Computer is free from
problems like lack of concentration,
and confusions & tiredness.
5. Versatility: We can perform
different types of tasks on computer.
It is therefore versatile in nature.
6. Power of Remembrance: Unlike
humans, computer can store things
for unlimited period of time.

7. Types of Computer
There are two basic kinds of computers:
• Analog Computer
• Digital Computer
• Hybrid computer

8. Analog computers
 Analog computers are analog devices.
That is, they have continuous states
rather than discrete numbered
states.
 An analog computer can represent
fractional values exactly, with no
round off.
 They handle or process information,
which is of physical nature.
 Examples: Computers in Chemical
plants monitoring temperatures,
pressures, voltage, etc.
Now these days, we rarely came across of analog
computers in routine life.

9. Digital Computer
 A digital computer uses discrete
states.
 A binary digital computer uses
digits and process data, which is
essentially in a binary state.
 Example: Personal Computers,
scientific calculators, etc.

10. Hybrid Computer
 It refers to computer that contain
both digital and analog circuit.
 For Example: A digital
thermometer converts the
temperature (analog signals) and
gives the output of measurement in
digits (digital signal)

11. Classification of Computer
• Micro Computer
• Mini Computer
• Mainframe Computer
• Super Computer

12. Micro Computer
 Micro computer is general purpose
computer, it is also called Personal
Computer (PC).
 It uses microprocessor, CPU for
manipulating data.
 It is smaller than Mini Computer,
Mainframe Computer and Super
computer.
 It has storage capacity up to Terabytes
(TB)
 It is used in general purpose.
 Example: IBM PC, Apple Macintosh,
Sony VAIO, etc.

13. Mini Computer
• Mini computer is smaller than
Mainframe and Large than micro
computers.
• It is cheap than mainframe
computers.
• It has storage capacity less than
micro computers.
• Examples: Data General, Wang
Laboratories, Apollo Computer,
and Prime Computer.

14. Mainframe Computers
 Mainframe Computers are very
powerful large-scale general-
purpose computers.
 It’s memory capacity is in
megabytes (MB) and storage
capacity is in terabytes (TB).
 They are used where large amount
of data are to be processed.
 Examples are: IBM 4300 series, IBM
Enterprise, System/9000 series

15. Super computer
 A supercomputer is a computer
which has high processing
capacity – particularly speed of
calculation.
 It has high storage capacity in
Petabyte (PB).
 It has number of CPUs to make
more speed.
 Example: IBM roadrunner, Cray
Jaguar, Cray Titan, IBM Sequoia,
etc.

16. Advantages & Disadvantages of Computer
Advantages
• It makes our work easier,
faster and accurate.
• It saves our cost and time
while collecting,
manipulating and storing
large amount of data
• It helps in worldwide
communication.
Disadvantages
• It is harmful to health, it
affects eyesight and
backbones if we work too
long.
• It creates unemployment.
• It makes people dumb and
dull.

17. The
End