What is a computer peripheral?

External devices, referred to as "peripherals," are hardware devices that are not connected to the computer's mainframe. The role of data and information transmission, transfer and storage is an important part of computer system.

With the rapid popularization of computer applications and the increasingly extensive application of network and information, the demand of computer external equipment is increasing, which has led to the formation and rapid development of computer external equipment industry in China. Today, some products have formed a large-scale production and occupy a certain market share. It is expected that in the next few years, China's computer external equipment industry will develop its own core technology, cultivate its own brand, improve product cost performance, expand production scale, increase industry application solutions and so on, and is expected to compete with international brands in certain product areas.

Due to the wide range of external equipment, some equipment has a variety of functions, so far, it is difficult to make accurate classification of external equipment. According to the function of different, roughly can be divided into input equipment, display equipment, printing equipment, external memory and network equipment five categories.

Input device

An input device (input Device) is a device that interacts with a computer in person or outside, and is used to enter raw data and programs that process the data into the computer. Now the computer can receive a variety of data, can be numeric data, but also can be a variety of non-numeric data, such as graphics, images, sounds, etc. can be entered into the computer through different types of input devices, for storage, processing and output.

Display device

Displaying devices in a computer output device is the equivalent of our eyes, we want to know if the operation is correct and what the result is, usually by the display device to observe. At present, the computer display equipment mainly has CRT display, LCD display, plasma display and projector. The main use for microcomputers is CRT monitors and LCD displays.

Printing devices

A printer (printer) is one of the output devices of a computer that is printed on a piece of paper in accordance with a prescribed format, such as numbers, letters, symbols, and graphics, that are the result of a computer's operation or intermediate results. There are a lot of types of printers, according to the printing element to the paper whether there is a strike action, split-hit printer and non-hit printer; According to the print character structure, the whole-word printer and dot-matrix character printer; In the form of a line of words on paper, string-type printers and line printers; According to the technology used, column, spherical, ink-jet, Heat-sensitive, laser-type, electrostatic, magnetic, light-emitting diode-type printers. There are three indicators for measuring the quality of a printer: print resolution, printing speed and noise.

External memory

External memory is a device used to store information such as instructions and data that are not directly associated with an operator in a computer. It was originally used to expand the capacity of computer memory, but with the change of machine architecture, it became an indispensable part in the random storage system of on-line timing and time-sharing system, most of the information of software and data was stored in high speed.

The external memory keeps information for a long time and does not rely on electricity to save information. But driven by mechanical parts, the speed is much slower than memory. The external memory does not exchange information directly with the operator and the controller, but under the control of the processor, the required data and program are sent to the internal memory at any time by the external control part, and the result of the operation is stored. This solves the contradiction between the speed and the capacity and the cost.

Network equipment

For high-speed and accurate information transmission, to achieve resource sharing and improve computer utilization, many computer systems are often connected to computer networks through specialized equipment and communication lines. With the rapid development of computer technology, computer network has penetrated into all areas of society, closely related to our lives. Network control the development of social economy, also make people's work and way of life has undergone great changes. When connecting computers with computers, workstations and servers, in addition to the use of connected media, network transmission media interconnection equipment, network physical layer interconnection equipment, data link layer interconnection equipment, network layer interconnection equipment and application layer interconnection equipment, and so on five kinds of intermediary equipment.