BIOS (Basic Input/Output System)

en.wiktionary.org/wiki/BIOS

Stands for “Basic Input Output System.” This program is found on all Windows based machines, and is used to start the computer up. BIOS is not used in Mac systems.

The program built into a computer to control its operation, especially the booting of an operating system. Most computers let the user configure various BIOS options by means of a special screen or set of screens.
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