BIOS Full Form is Basic Input/Output System. BIOS denotes the software, which is stored in the tiny memory chip in the motherboard of a computer. It is the software that helps in booting process once the power is on. This software is offered as a part of personal computers to aid booting. BIOS is also called ROM BIOS or System BIOS or PC BIOS.
Once a PC is switched on, BIOS sends instructions for it to perform all basic functions like booting, keyboard control, and more. BIOS also helps in identifying and configuring the hardware of the system such as; floppy drive, CPU, hard drive, memory, optical drive, etc. Each BIOS implementation is specifically designed for it to work with specific motherboard or computer model. Conventional computers had BIOS stored in the ROM chips of motherboards. The modern systems have BIOS contents stored in the flash memories.