Classification of Computer

computer are classified on the basis of size,speed ,processing power and price.however,
the classification of computers is not very straight-forward.the distinction between these
categories is sometimes not very clear. some characteristics overland different categories.
computer can be divided into the following categories:
>microcomputer or personal computer
>minicomputer
>mainframe computer
>super computer
>embedded computer

Microcomputers:-
microcomputer is also called personal computers.It was introduced in 1970.it is designed to
be used by one person at a time.it consists of a processor,memory and one or more input,
output and storage devices.It also often contains a communication device.The price of
personal computer is from several hundreds to several thousand dollars.Most commonly
used personal computers are PC and Apple .PC and its compatible computers used
windows operating systems.The term OC compatible means any personal computer based
on the original IBM personal computer design.Apple computers use Macintosh operating
system. the major types of personal computer are desktop computer and portable computer.

(i)DESKTOP COMPUTERS:-

Desktop computers are the most  common type of personal computer.it is designed in a
way that all its components fit on desk or table.In one model, the system unit is placed 
horizontally on the desktop or table monitor is placed on the table. system unit in tower
model is placed vertically.
(ii)PORTABLE COMPUTER 
portable computer is a personal computer that can be carried from one place to other
easily.Different types of portable computer include notebook computers,tablet PC and
handheld computers.
1:-NOTEBOOK COMPUTERS
Notebook computer is also called laptop computer.It is a portable personal computer that
can be placed on lap easily.It is more expensive than desktop computer.Is is thin and light
weight.It uses less power and can be used with batteries. Only.Only one user can be use
them at a time.A notebook computer can perform the same basic functions as a personal
computer The computing power of modern notebook computers are nearly equivalent to
personal computers.The price of these computers is from $1000 to $2500.
Net Book:-
Netbook is a small,light and inexpensive laptop computers.Is is suited for general computing
and web-based applications.It provides reduced computing power as compared to a full-size
laptop computer.
2:-TABLET PC
Tablet PC is a special type of notebook computer. It is used to writ or draw on screen using
a special digital pen or stylus.Some tablet PCs have an attached keyboard and some allow
the user to connect a separate keyboard.It also supports voice input to enter text and give
instructions by speaking it is used to take notes in lectures, meetings and conferences.
3:-HANDHELD COMPUTERS
Handheld computers is also called palmtop computer.It easily  fits in the hand of the user.
It contains small screen and small keyboard.keyboard. Handheld often use stylus as input
device to enter data.Some handheld computers also support voice input.Handheld computers
usually have no disk drive.The programs and data are stored on chips in the system unit.
Handheld computer is not powerful as compared to desktop and notebook computer.
 USE OF MICROCOMPUTER:-
Micro computer is  the most common type of computer used in the office and at home.It is
also used for business and engineering application. 
Minicomputers:-
 Minicomputer can serve up to several hundreds connected computers simultaneously.
It is normally accessed by users through personal computer or terminal.It is also with a 
monitor and keyboard is called terminal it is also called dumb terminal.It has no processing 
power and cannot work as stand-alone computer.It has to be connected to a server.
EXAMPLES:
Prime 9955
HP 3000
AS 400
VAX 8600 
Mainframe Computers:- 
A mainframe computer is a large computer in terms of price,power and speed.It was 
introduced in 1975.It is more powerful than mini computer.It consists of multiple 
processor.It is specially designed to perform multiple tasks for multiple users simultaneously.
It is designed for high reliability. is is also known as enterprise server or high-ended server.
Mainframe computer can serve several thousand users simultaneously. these computers can 
store  large amounts of data .information and programs.The users access a mainframe 
computer through a terminal or personal computer.The price of mainframe computer is 
several thousand dollars and can be up to several million dollars IBM,Sun and Unisys are 
leading manufacturers of mainframe computers.
EXAMPLE
>IBM S-390
>NEC 610
>DEC !)
>IBM System Z10
Uses of Mainframe Computers:-
mainframe computers are used in large organizations such as banks,educational institutions
and govt.departments.For example,airlines use these computers to maintain flight schedules,
ticket reservation system etc.
Supercomputers:-
Supercomputer is the fastest and the most powerful computer.It is the biggest in size and the
most expensive in price than any other computer.It was first developed in early 1970s. It is
used to perform complex tasks.It has a very large storage capacity and can store several
thousand times more data than average desktop computer.It can process trillions of instruction
in one second .The modern super computer consists of thousands of microprocessors.The
cost of one supercomputer can be up to several billion dollars.
EXAMPLE:-
Roadrunner
Blue Gene
Deep blue
ASCI White
Uses of Supercomputers
Supercomputer is mostly used for weather predication,weapon design and atomic research etc.Supercomputer is also used in business and industry field.Aircraft manufacturers use it to
simulate aircraft and check its performance.Government use a supercomputer for different
calculations and heavy jobs.Many Hollywood movies use it for animation purposes.

Embedded computers:- 

AN embedded computer is designed for special purposes.It works as a component in a 
larger product. these computers are very small and have limited hardware.They perform 
various functions according to the requirements of the product in witch they are embedded.

Embedded computers are used in commonly used products such as.
* Electronics :PDAs,Mobile,Video recorders and DVD players etc.
* Home Devices:Security monitoring system & programmable microwave ovens etc.
* Automobiles:Car engine controller.airbag controller etc
* Process Controllers and Robotic:Machine controllers.blood pressure monitors etc.