What Is Basic Input/Output System?

The Basic Input/Output System (BIOS) is a program stored on a motherboard's memory chip that enables users to access and set up a computer system. BIOS provides instructions to the CPU when you boot a computer, but it also manages the data flow between the OS and attached devices (hard disks, keyboards, printers, etc.). Other common names for BIOS are System BIOS, ROM BIOS, and PC BIOS.