What is BIOS?
BIOS is basic startup software built into a computer’s motherboard. It checks the hardware and helps the computer begin loading the operating system.
In more detail
BIOS stands for Basic Input/Output System. It is low-level software stored on a computer’s motherboard that runs as soon as the machine is powered on.
Its main job is to check that key hardware parts like the keyboard, memory, and storage are working, then start the process of loading the operating system. Without BIOS, a computer would not know how to begin startup.
For everyday users, BIOS matters because it controls important startup settings, such as boot order, hardware detection, and some security options. On many newer computers, BIOS has been replaced or updated by a similar system called UEFI, but people still often use “BIOS” to mean the startup firmware in general.
Examples
- Changing the boot order so a computer starts from a USB drive.
- Checking whether the system recognizes installed RAM or a hard drive.
- Turning on or off features like secure boot or fan settings.
- Entering the setup screen when the computer first powers on.
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