Central processing unit
electronic circuitry within a computer that carries out the instructions of a computer program by performing the basic arithmetic, logical, control and input/output (I/O) operations specified by the instructions and coordinates the other components / From Wikipedia, the free encyclopedia
A central processing unit (CPU) is an important part of every computer. The CPU sends signals to control the other parts of the computer, almost like how a brain controls a body.
The CPU is an electronic machine that works on a list of computer things to do, called instructions. It reads the list of instructions and runs (executes) each one in order. A list of instructions that a CPU can run is a computer program.
The clock rate, or speed of a CPU's internal parts, is measured in hertz (Hz). Modern processors often run so fast that gigahertz (GHz) is used instead. One GHz is 1,000,000,000 cycles per second.
Most CPUs used in desktop (home) computers are microprocessors made by either Intel or Advanced Micro Devices (usually shortened to AMD). Some other companies that make CPUs are ARM (recently bought by Nvidia), and IBM. Most of their CPUs are used in embedded systems for more specialized things, like in mobile phones, cars, video game consoles, or in the military.