what is Arithmetic and Logic Unit

ALU (Arithmetic and Logic Unit)

ALU is a part of CPU. Actual execution of instructions takes place in this part. All

arithmetic and logical operations are performed in ALU. It consists of two following units.

                                                          

i. Arithmetic Unit

ii. Logic Unit

i. Arithmetic Unit

Arithmetic unit of ALU performs basic arithmetic functions such as

addition, subtraction, multiplication and division.

ii. Logic Unit

Logic unit of ALU performs logical operations like comparing two

data items to find which data item is greater than, equal to, or less

than the other.

2. Control Unit

Control unit is an important component of CPU. It acts like a supervisor of the

computer. It does not execute program instruction by itself. It controls and coordinates all

activities of computer system. It performs this task by issuing necessary commands to

different component of computer. Control unit also provides clock pulses that are used to

regulate and control all operations in the computer system.

Important operations performed by control unit are as follows:

1. It fetches instructions from the main memory.

2. It interpret the instructions to find what operation is to be performed.

3. It controls the execution of instructions.