Types of computer
A computer may be defined as a device which will accept input data, process it according to certain rules and stores or outputs data.
Computers have traditionally been classified as supercomputers, mainframes, minicomputers and microcomputers (or PCs), but the distinctions are less distinct with modem systems. A computer is a device which will accept input data, process it, and store or output the results.
Types of computer:
Computers can be classified as follows, starting with the most powerful.
• Mainframe computers, now sometimes called enterprise servers’
• Minicomputers, now often called ‘mid-range’ computers
• Microcomputers, now commonly called Personal Computers (PCs)
able to process very large amounts of data very quickly. They are used for very complex calculations, for example by astronomers tracking the movement of objects in outer space. Manufacturers of supercomputers include Cray and Fujitsu.
After supercomputers, the next most powerful computers are mainframes. A mainframe is a very powerful computer often used at the centre of a large computer system. The mainframe is linked by cable or other telecommunications links to a number of terminals. A mainframe has significantly more processing power than a PC and offers very extensive data storage facilities. Some people now refer to mainframes as ‘Enterprise servers’. Manufacturers include IBM and HP.
The term ‘minicomputer’ is sometimes used to describe a computer that has more processing power than a PC, but less than a mainframe.
The term isn’t used very often now, as with the development of more powerful PCs and physically smaller mainframes, it is difficult to define exactly what a minicomputer is. Price, power and number of users supported are sometimes used as distinguishing features. Manufacturers of minicomputers include IBM, ICL and DEC.
• Personal computers (PCs)
The most common type of computer is the Personal Computer or PC. A PC is a general-purpose, single-user computer designed to be operated by one person at a time. The technical name for a PC is a microcomputer.
PCs are now the norm for small to medium-sized business computing and for home computing. Often they are linked together in a network to enable sharing of information between users.
The physical components of a typical Personal Computer (PC) are shown in the following diagram.