Atone of the component of the microprocessor, the circuit which does arithmetic processing such as arithmetical operation and logical operation.

Other than the circuit which does operation, it consists the accumulator which keeps the operational result and the like temporarily and the flag register etc. which keeps the status information of plus and minus and the beam rising etc. of the operational result.

The microprocessor, other than ALU, consists of the controlcontrol equipmentand the register, the clockgeneratorand the bus etc..