“When a computer first boots, it starts up the BIOS (Basic Input-Output System), a sort of rudimentary operating system designed to work (hopefully) without user intervention. Its purpose is to find and activate the bare minimum hardware needed to allow the discovery and activation of an operating system that is actually designed to interact with the user. The BIOS provides a central sort of abstraction that accepts input from various devices and offers output interfaces from which devices can receive data. This allows your computer to trade information between components so that the processor can access an operating system on your boot media (hard drive, floppy disk, et cetera), load necessary bits of it into memory, and ultimately begin running software so that it interacts with humans in the real world in some way.”

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