The BIOS software has most important role is to load the operating system. Such as when you turn on your computer and the microprocessor tries to execute its first instruction, it has to get that instruction from somewhere. The BIOS provides those instructions. The other common tasks that the BIOS performs include:
- A power-on self-test (POST) for all of the different hardware components in the system to make sure everything is working properly
-Activating other BIOS chips on different cards installed in the computer
-Providing a set of low-level routines that the operating system uses to interface to different hardware devices. Such as the keyboard, the screen, and the serial and parallel ports etc.
-Managing a collection of settings for the hard disks, clock, etc.