BIOS stands for Basic Input Output System. It is a firmware that is stored on a small memory chip on the motherboard. It’s responsible for the POST and therefore makes it the very first software to run when a computer is started. BIOS instructs the computer on how to perform basic functions such as booting and keyboard control. BIOS is also used to identify and configure the hardware in a computer such as the hard drive, floppy drive, optical drive, CPU, memory, and related equipment