Classification of Computer

 Types of Computer Based on Signal Processing

1. Analog Computer:

Analog computer is that computer, which is use to process continuously varying data. Everything we see and hear is change continuously. This changeable continuous stream of data is called analog data. Analog computer can be used in scientific and industrial applications such as measure the electrical current, frequency and resistance of capacitor, etc.

 

2. Digital Computer:

These are high speed electronic devices. These devices are programmable. They process data by way of mathematical calculations, comparison, sorting etc. They accept input and produce output as discrete signals representing high (on) or low (off) voltage state of electricity. Numbers, alphabets, symbols are all represented as a series of 1s and 0s.

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.

-          The first desktop hybrid computing system was the Hycomp 250, released by Packard Bell in 1961.

Types of Computer Based on Speed and Size

Computer on the basis of Size can be classified into 4 major types:

 

1.      Super Computer

-          Super computers are the fastest, most-powerful and most expensive computers.

-          It has the ability to recover automatically from failures.

-          It has the ability to support several Giga Bytes of RAM.

-          Unlike conventional computers, which have a single processor to process one instruction at a time, supercomputers have multiple processors (or CPUs) that process multiple instructions at a time.

-          Supercomputers are widely used in scientific applications such as aerodynamic design and simulation, processing of geological data.

-          One of the most powerful supercomputers today is “The Cray-2” and some others are CRAY 1, CRAY-MP, SX-2, HITAC S-300, etc.

 

 

2.      Mainframe Computer

-          A mainframe computer is usually slower, less power and less expensive than supercomputers.

-          Very large in size with approximately 1000 square ft. area.

-          Mainframe process several million instructions per second (MIPS). More than 1000 remote workstations can be accommodated by a typical mainframe computer.

-          Mainframes are used by banks and many more business to update inventory, etc.

-          Many modern mainframe have multiprocessing capabilities.

-          E.g. IBM 4300 series, IBM 308X series, HP 9000 etc.

 

3.      Mini Computer

-          These are also a general purpose computer, smaller than mainframe computer. Medium sized computer, occupying approximately 10 sq ft of area.

-          They have slower operating speed, smaller backup storage, limited hardware and less memory than mainframes.

-          Minicomputers are well adapted for functions such as accounting, word processing, database management, statistical packages for social sciences.

-          More than 50 terminals and large storage capacity device than microcomputers but smaller than mainframe computers. E.g. Prime 9755

 

4.      Micro Computer

-          A microcomputer is the smallest, least expensive of all the computers.

-          Microcomputers have smallest memory and less power.

-          Microcomputers are also called personal computers.

-          The most common type of microcomputer is a desktop computer, which is a non-portable personal computer.

-          E.g. Desktop, laptop, notebook computers etc.