The processor is the brain of the computer. It is responsible for performing calculations and tasks that make programs work. The processor is the most important component of a computer, but it is also one of the most expensive. The processor is made up of millions of tiny transistors that are used to perform calculations. The speed of the processor is measured in gigahertz (GHz), which is a measure of how many calculations it can perform in one second. The faster the processor, the faster the computer will be able to run programs.