BIOS

BIOS is the program stored in Read Only Memory (ROM) that gets your computer started when it’s turned on. The purpose of the BIOS is to initialise and test the system hardware components and to load the operating system from the hard disk into RAM.


POST (Power on self test)

When the computer power is turned on the POST runs a test sequence to check the computer's input/output systems (mouse, keyboard, monitor, RAM, disk drives etc) are working correctly.


Boot loader (Bootstrap)

A program that runs as soon as the computer is powered on which starts the Operating System (loads it from the hard drive to RAM and gets it running).




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