The document describes the main parts of a CPU including a control unit, immediate access store, backing store, arithmetic and logic unit, and inputs and outputs. The control unit directs operations, the immediate access store holds frequently used data, and the backing store holds longer term storage while the arithmetic and logic unit performs calculations.

1. Control Unit
Immediate Access Store
Backing Store
Arithmetic
& Logic
UNIT
(ALU)
Parts of a CPU
Control Unit
Inputs & Outputs