This document summarizes different types of computers based on their purpose, data handling abilities, and functionality. It describes general purpose and specific purpose computers, analog, digital, and hybrid computers. It also discusses different types of computers like supercomputers, mainframes, desktops, laptops, palmtops, and workstations. The document concludes by describing the basic components of a computer including memory, storage devices, input/output devices, the central processing unit, and its main components like the arithmetic logic unit and control unit.

1. Mrs. Sudhaa Ravichandran M.Sc,M.Phil
Assistant Professor ,
Department of Computer Science
Selvamm Arts and Science College,
Namakkal.

2. Computers differ based on their data
processing abilities. They are classified
according to purpose, data handling and
functionality.
According to purpose, computers are
either general purpose or specific
purpose. General purpose computers are
designed to perform a range of tasks.

3. They have the ability to store
numerous programs, but lack in speed
and efficiency. Specific purpose
computers are designed to handle a
specific problem or to perform a
specific task. A set of instructions is
built into the machine.
According to data handling, computers
are analog, digital or hybrid.
According to functionality,

5. Analog Computer
 An analog computer is a form of
computer that uses continuous physical
phenomena such as electrical,
mechanical, or hydraulic quantities to
model the problem being solved.

6. Digital Computer
 A computer that performs calculations and logical
operations with quantities represented as digits, usually in
the binary number system

7. Hybrid Computer (Analog + Digital)
 A combination of computers those are capable of
inputting and outputting in both digital and analog
signals. A hybrid computer system setup offers a
cost effective method of performing complex
simulations

8. Super Computer: Large in size and
more powerful. Used for large and
complex calculation.
• Mainframe Computer: Mainframe
computers are smaller than super
computer. It has large storage capacity
and capable to perform large
calculation. Used in bank,
educational institution.

10. Desktop Computer: a personal or
micro-mini computer sufficient to fit
on a desk.
Laptop Computer: a portable
computer complete with an integrated
screen and keyboard. It is generally
smaller in size than a desktop
computer and larger than a notebook
computer.

11. Palmtop Computer/Digital Diary
/Notebook /PDAs: a hand-sized computer.
Palmtops have no keyboard but the screen
serves both as an input and output device.
Workstations
A terminal or desktop computer in a
network. workstation is just a generic
term for a user's machine (client
machine) in contrast to a "server" or
"mainframe."

12. • Memory: It is a physical device
(integrated circuits or chip) that enables a
computer to store data and programs
temporarily or permanently. It is also term
as "primary storage".
• Mass storage device (MSD): It is used
to store large amounts of data for example
hard disks, USB drive, CD-ROM etc.

13. • Input device: It is any hardware device
like keyboard and mouse that sends data
to a computer.
• Output device: It is a device that sends
data from a computer to another device.
• CPU (Central Processing Unit): It is
also referred to as a processor or brains of
a computer that carries out the
instructions of a computer system.

15. Central Processing Unit
The various activities that a
microprocessor performs, such as storing
data, doing arithmetic calculations
(addition, subtraction, multiplication,
division, etc.), are the result of
instructions given to the CPU in the form
of sequences of 0s and 1s.
Microprocessors are designed to carry
out a large number of instructions and all

16. instructions may be represented by different
sequences of 0s and 1s. Each instruction is
represented by a unique set of 0s and 1s.
The internal structure of a typical CPU
consists of circuits which form a number
of registers (the typical number is 16), an
arithmetic unit for carrying out arithmetic
operations, a logic unit, and a control unit.

17. Arithmetic logic unit (ALU)
Arithmetic Logical Unit is used for
processing data after inputting data is
stored into primary unit. The major
operations of Arithmetic Logical Unit are
addition, subtraction, multiplication,
division, logic and comparison.

18. Control unit (CU)
It is like a supervisor, that checks
ordaining operations or check
sequence in which instructions are
executed.

19. Thank you