ALU - Arithmetic Logic Unit

Arithmetic Logic Unit is another important component of CPU. It performs the mathematical and logical operations on the data. When the control unit encounters instruction related to perform arithmetic or logical operation on data, it passes that instructions to ALU. 

It is responsible for doing all types of arithmetic operation like addition, subtraction, multiplication and division on integer and real operands. It also can perform the logical operation or comparison like equal to, greater than, less than etc. between two operands. It receives its operands from the register section of the CPU and stores its results back in the register section.