Control unit may refer to:
Control unit, a component of a computer's central processing unit
The control unit is a component of a computer's central processing unit (CPU) that directs operation of the processor. It tells the computer's memory, arithmetic/logic unit and input and output devices how to respond to a program's instructions.
Another name for a Controller
In computing and especially in computer hardware, a Controller is a chip, an expansion card, or a standalone device that interfaces with a peripheral device.
Fonte: Wikipédia