BIOS

BIOS stands for Basic Input Output System. This term defines a firmware interface. It is also sometimes referred to as System BIOS. The BIOS falls in the category of boot firmware, and contains the code which is the first code to be run when a computer is switched on. The basic function of BIOS is to identify the devices installed on your PC, test them for correct functionality and then initialize them for future processes to be executed. The BIOS prepares the system to a known state, and helps the software that is stored on compatible media to be loaded, executed and handed control of the PC.

BIOS programs are stored on a chip and are built to work with various devices that make up the complementary chipset of the system. They provide a small library of basic input/output functions that can be called to operate and control the peripherals such as the keyboard, text display functions and so forth.

A computer system motherboard may contain more than one BIOS chips. The BIOS normally contains code that has access to standard computer hardware such as keyboard, storage devices, device controllers, floppy drives, CD ROM drives and many others.