The peripheral device is a component or a device that is located outside the central processing unit of a computer (short: accessory). In simplified terms, a distinction can be made between (internal ) peripheral devices built into the computer and (external) peripheral devices connected to it by a cable (or by infrared or radio technology ).
Peripheral devices are used to input and output data or commands to the central unit. They provide a "service" for the user, this can be done either visibly (e.g. paper printout) or invisibly (e.g. signal conversion of internal modems).
The assignment as internal or external peripheral devices is not always clear. In some cases, accessory devices are also subject to a change in meaning. For example, network cards used to be available externally as expensive special accessories for mobile devices and sometimes also for desktop computers . Today, external models have practically disappeared from the market because they are part of the motherboard as common standard devices . The floppy disk drive, on the other hand, has almost disappeared from the market and is only used externally as a special accessory on newer computers. Some earlier notebook models (e.g. Compaq Contura series ) were supplied with a trackball instead of a touchpad , but the trackball was not able to establish itself on the mass market as an internal peripheral device. However, it is an externally connected niche product in the industrial sector (dusty factory buildings, vandalism-proof use) . The assignment below therefore relates to the usual use of today's models.
Input and output devices
Peripherals are divided into input and output devices. Multifunctional devices can also be counted as a type of peripheral device. For input devices you can z. E.g. keyboards, mice, scanners and microphones count. Output devices include screens, projectors, plotters / printers and speakers. A printer with a scan function or the touchscreen can be described as multifunction devices.
External or internal peripherals
- Sound card
- Internal or external hard drive
- RAID controller
- USB hub
- CD-ROM , DVD , or BD-ROM drive; or burner
- Floppy disk drive
- TV card
- Bluetooth or infrared USB interfaces
- Loudspeaker and microphone (internal usually only on mobile computers)
- Modem , e.g. B. UMTS modem
- Memory card reader
- Touchpad and trackball