<hardware> (Or "peripheral device", "device") Any part of a computer
other than the CPU or working memory, i.e. disks, keyboards, monitors, mice,
printers, scanners, tape drives, microphones, speakers, cameras, to list just
the less exotic ones.
High speed working memory, such as RAM, ROM or, in the old days, core would not
normally be referred to as peripherals. The more modern term "device" is also
more general in that it is used for things such as a pseudo-tty, a RAM drive, or
a network adaptor.
Some argue that, since the advent of the personal computer, the motherboard,
hard disk, keyboard, mouse, and monitor are all parts of the base system, and
only use the term "peripheral" for optional additional components.
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