The processor (really a short form for microprocessor and also often called the CPU or central processing unit) is the central component of the PC. It is the brain that runs the show inside the PC. All work that you do on your computer is performed directly or indirectly by the processor. Obviously, it is one of the most important components of the PC, if not the most important. It is also, scientifically, not only one of the most amazing parts of the PC, but one of the most amazing devices in the world of technology.