An Etymological Dictionary of Astronomy and Astrophysics

The primary component of a → computer that processes instructions. It runs the → operating system and → applications, constantly receiving input from the user or active → software programs. The CPU has two typical components:

1. Control Unit, which extracts instructions from memory and decodes and executes them.
2. Arithmetic Logic Unit (ALU), which handles arithmetic and logical operations.

See also: → central; → processing; → unit.