The BIOS chip is non-volatile, which means it "remembers" its information even when your PC is turned off. This chip fills two roles. First, it's like the starter on your car engine. The BIOS starts your PC and gets it running. In technical terms this is called booting your PC.

Second, once your PC is running, the BIOS acts like your cookbook. It contains the "recipes" or instructions that allow the CPU to talk all the peripheral devices connected to your PC such as the monitor and keyboard.