CPU stands for central processing unit (CPU) is the 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. It is the brain of the computer. There are major two brand of pc cpu. AMD and INTEL, they were really close in performance;but in recent years, Intel pull it off by less power consumptin, moer speed and better in real world.

A graphics processing unit (GPU), also occasionally called visual processing unit (VPU), is a specialized electronic circuit designed to rapidly manipulate and alter memory to accelerate the creation of images in a frame buffer intended for output to a display.