BIOS

Firmware for hardware initialization and OS runtime services

In computing, BIOS or the Basic Input/Output System is a type of firmware used to provide runtime services for operating systems and programs and to perform hardware initialization during the booting process (power-on startup). On a computer using BIOS firmware, the firmware comes pre-installed on the computer's motherboard. The name originates from the Basic Input/Output System used in the CP/M operating system in 1975.

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