Type of Computers

Type of Computers

Different types of computers can be classified as:

• Micro Computers/PCs
• Mini computers
• Mainframe Computers
• Super Computers

The above classification of computers is based on the internal memory and speed of processing.

MICRO/PERSONAL COMPUTERS (PCs)

Micro computers have brought revolution in the industry of computers because of their size and cost. All PCs came under micro computers are:

*Cheap and easy to use.

*Have limited input/output capacities.

*Limited range of software can be used.

*Have low storage capacity.

* Designed to be used by one person at a time.

*Have CPU and a keyboard for input.

*Hard disk and floppy disk drives are used to enter and store data and programs.

*Monitor and printers are used to get the output.

MINI COMPUTERS

Mini computers are less efficient and store less data than mainframe computers. The main characteristics of mini computes are:

*Have limited range of peripherals.

*Limited software’s are used 

*Can be directly operated by the user.

*Air conditioning is not necessary and is provided in many cases only for dust control.

*Minicomputers are used widely for data processing and industrial applications.

Mainframe Computers 

Mainframe Computers are very large computers.

E.g. IBM 390. The main characteristics are:

*Based on the principle that computing power should be concentrated.

*Many people can make sure of the same machine at the same time.

*Support a wide range of peripherals.

*Sensitive to variations in temperature, humidity, dust etc.

*Qualified operators and programmers are required for the operations.

* Have large storage capacity.

*Can make use of a wide variety of software.

Super Computer

Super computers are largest, fastest and most expensive computer systems in the world. They are used to process complex scientific jobs. The common characteristics of super computer are:

*Based on the concept of paralleled processing.

*Many small computer chips work simultaneously to perform millions of arithmetic operations per second.

*Mainly being used for weather forecasting, remote sensing, image processing, bio-medical applications etc.

There are a number of manufactures who dominate the market of super computers.

CORAY (CRAY, YMP, CRAY2), ETA (EDC-ETA 10, ETA20) and IBM 3090, NECNEC sx-3).

                  In India, we have one such mainframe super computer system CRAY XMP-14, which is at present being used by Meteorological Department.

Computer Capabilities

Most people know that a computer is a fast calculator, but it is much more than that. It is also a machine that can perform such burdensome chores as choosing, copying, moving, comparing, and performing other non-arithmetic operations on the many alphabetic, numeric and other symbols that we all use to represent things.

SPEED

A computer works one step at a time. It can add and subtract numbers, compare letters to determine alphabetic sequence and move and copy numbers and letters. It can perform millions of calculations in fractions of second, say in Nano seconds.

ACCURACY AND RELIABILITY

In addition to being very fast, computers are very accurate. If the input data entering the computer are correct and if the program of instructions is reliable, then we can expect that the computer generally will produce accurate output.

VERSATIL