Boot loader

A boot loader is a special program that starts up when you turn on your computer. It is responsible for loading and starting up the operating system and all of the other programs you use. It runs before anything else on your computer, so it needs to be very small and efficient. The boot loader is usually stored in the computer's Basic Input/Output System (BIOS), which is a program that is built into the computer's hardware. The BIOS finds the boot loader and runs it, then the boot loader finds the operating system and runs it. This is how your computer knows what to do when you turn it on.