Types of Computer

A computer is a device that takes in data, processes it according to a program, and then outputs the processed data in some form. There is an increasing variety of computers of different sizes and designed for different purposes. One of the most important considerations when buying a computer is deciding how it is going to be used.

Computers can be divided into three broad categories: mainframe computers(mainframes),minicomputers (minis), and microcomputers (micros). Mainframes are large, powerful, expensive computers that are operated by a team of professionals and are designed to be used by many people at the same time. The most powerful mainframes are sometimes called supercomputers. Minicomputers are really cut-down mainframes and are no longer very common.

The most common type of computer is the microcomputer. Microcomputers are sometimes called personal computers. The abbreviation PC was originally used for microcomputers produced by the IBM Corporation, but it is now sometimes used for other types of personal computer. However, microcomputers produced by Apple Computers Incorporated are not normally referred to as PC.

There is a wide variety of microcomputers but two common types are desktop computers and portables. Desktops are small enough to sit on an office desk and are relatively cheap. They are becoming cheaper and more powerful and are often used running multimedia programs, i.e. programs that contain some combination of text, sound, high quality graphics,animation and video. Multimedia computers need to have a sound facility and usually have a CD-ROM or DVD drive.

There is an increasing variety of portable micros that can be grouped according to their size. They can usually be powered from batteries and are useful in many different situations. However, as computer gets smaller, it becomes increasingly difficult to use them with a keyboard. One of the reasons that notebook portables are popular is because their screens and keyboards are just big enough to use comfortably for word processing. They can also be powered enough to be used for multimedia.

The most common types of computers are indicated here on the blackboard, although there are other types that are not mentioned here and new types are being developed.

Electronics can be added to desktop computers by plugging in expansion cards (electronic circuit boards that can be plugged into special sockets called expansion slots). It is also possible to build all the main parts of a computer into one electronic integrated circuit packaged as a single electronic chip (the common name for a microchip; an electronic integrated circuit in a small package) i.e. “the computer on a chip”. This enables computers to be built into other devices including household devices such as washing machines and fridges and to be incorporated into plastic cards i.e. smart cards, which are able to store information such as health records, drivers’ licences, bank balances, etc. Devices that include a computer circuit are commonly referred to as smart devices. A multimedia computer can process different forms of data including text, graphics, audio (sound), animation and video. This enables computer systems to be used for a combination of education and entertainment, sometimes referred to as edutainment.