CPU

Abbreviation of central processing unit, and pronounced as separate
letters. The CPU is the brains of the computer. Sometimes referred
to simply as the processor or central processor, the CPU is where
most calculations take place. In terms of computing power, the CPU
is the most important element of a computer system.

On large machines, CPUs require one or more printed circuit boards.
On personal computers and small workstations, the CPU is housed
in a single chip called a microprocessor.

Two typical components of a CPU are:

The arithmetic logic unit (ALU), which performs arithmetic and
logical operations.

The control unit, which extracts instructions from memory and decodes
and executes them, calling on the ALU when necessary.