A computer processor, also known as a central processing unit (CPU), is the main component of a computer that performs calculations and executes instructions. It acts as the brain of the computer, processing data and managing tasks. The speed and efficiency of a processor are measured in gigahertz (GHz), indicating how many cycles it can perform per second. Processors are made up of millions of tiny transistors that switch on and off to perform operations. They work closely with other components, such as memory and storage, to ensure smooth performance. Modern processors can have multiple cores, allowing them to handle several tasks simultaneously.