Page 16 - Computer Class 04

Processing in Computer

The CPU (Central Processing Unit) is the part of a computer system that is

commonly referred to as the ‘brain’ of a computer. The CPU is also known

as the processor or microprocessor. The CPU is responsible for executing a
sequence of stored instructions called a program .

8 Arithmetic Logic Unit (ALU) : It performs the arithmetic and logical

operations.
8 Control Unit (CU) : It controls the flow of input, process and output of

the computer.
8 Memory Unit (MU) : It stores the input and output data.

Arithmetic Logic Unit (ALU)

Input Output
Control Unit (CU)
Devices Devices

Memory Unit (MU)

Memory Unit

Memory is the most essential element of a computer system because
without it computer can’t perform simple tasks. Computer memory is of

two basic types– primary memory and secondary memory.

Primary Memory

Primary memory is also called the main memory or internal memory of the

computer. It is comprised of the memory devices RAM and ROM that are
necessary for working of a computer.

RAM (Random Access Memory) ROM (Read Only Memory)
It is the main memory that stores data This memory contains an unchange-

temporarily. The data remains in this able set of permanent instructions
memory until the computer is which appear on the screen when the

switched OFF. This memory is also computer is turned ON. This memory
known as a volatile memory . is also known as non-volatile memory .

Computer-4 16 Computer-1