Input Unit

It contains devices, which help us to enter data into the computer.

CPU

Central Processing Unit. It is the brain of the computer, which performs all kinds of processing operations. It consists of:

• Arithmetic & Logic Unit (ALU):
  It consists of arithmetic & logic section
  Arithmetic section performs all kinds of arithmetic operations, like addition, subtraction, multiplication, division and other complicated arithmetic operations.
  Logic section performs all kinds of logical operations, like comparison, selection merging of data and others.

• Memory Unit (MU):
  Also called storage unit. It does the following work:

1. It stores all the data and the instructions required for processing.
2. It stores intermediate results of processing.
3. It stores the final results of processing before these results are released to an output device.
4. All inputs and outputs are transmitted through the main memory.

• Control Unit (CU):
  It controls the operations of all parts of the computer. Its function includes:

1. It is responsible for controlling the transfer of data and instructions among other units of a computer.
2. It manages and coordinates all the units of the computer.
3. It obtains the instructions from the memory, interprets them, and directs the operation of the computer.
4. It communicates with input/output devices for transfer of data or results from storage.
5. It does not store data.

Output Unit

It consists of devices, which help us to get information from the computer.

Von Neumann Architecture | Computer Architecture