# Block-Diagram of Computer

### Block Diagram of Computer

Block Diagram of computer consisting various components they are:

• Input Unit
• Control unit(C.U)
• Memory unit(M.U)
• Arithmetic and logical unit (A.L.U)
• Output Unit.

Input: This is the process of entering data and programs into the computer system. You should know that computer is an electronic machine like any other machine which takes as inputs raw data and performs some processing giving out processed data.

CPU (Central Processing Unit): CPU is the heart of the computer. CPU performs all types of data processing operations. It stores data, intermediate results, and instructions (program). It controls the operation of all parts of the computer. The CPU again contains subunits. They are namely:

• ALU (Arithmetic and Logic Unit)
• Memory Unit
• Control Unit

Arithmetic and Logical Unit: All calculations are performed in the Arithmetic Logic Unit (ALU) of the computer. It also does comparison and takes decision. The ALU can perform basic operations such as addition, subtraction, multiplication, division, etc and does logic operations viz, >, <, =, ‘etc. Whenever calculations are required, the control unit transfers the data from storage unit to ALU once the computations are done, the results are transferred to the storage unit by the controls unit and then it is sent to the output unit for displaying results.

Control Unit: It controls all other units in the computer. The control unit instructs the input unit, where to store the data after receiving it from the user. It controls the flow of data and instructions from the storage unit to ALU. It also controls the flow of results from the ALU to the storage unit. The control unit is generally referred as the central nervous system of the computer that control and synchronizes its working.

Memory Unit: The process of saving data and instructions permanently is known as storage. Data has to be fed into the system before the actual processing starts. It is because the processing speed of Central Processing Unit (CPU) is so fast that the data has to be provided to CPU with the same speed.

Output Unit: The output unit of a computer provides the information and results of a computation to outside world. Printers, Visual Display Unit (VDU) are the commonly used output devices. Other commonly used output devices are floppy disk drive, hard disk drive, and magnetic tape drive.