central processing unit || CPU || definition and function || solo gyan

Introduction to CPU 

The CPU is the brain of a computer. Its primary job is to run program and control the operations of all other components, such as memory, keyboard, Mouse and printer etc. 

Central Processing Unit ( CPU ) consists of the following features - 

• CPU is considered as the brain of the computer.
• CPU performs all types of data processing operations.
• It stores data, intermediate results, and instructions ( Program).
• It controls the operations of all parts of the computer.

A block diagram of the basic computer organization is shown is figure. 

The Figure shows the basic arrangement of different units of a computer. It depicts the five major building blocks or functional units of a digital computer system. These five units correspond to the five basic operations, namely inputting, storing, processing, outputting and controlling data carried out by all computer systems.

Inputting:- 

Refers to the process of entering data into the computer, by the user using an input device, such as keyboard and mouse. 

Storing:- 

Refers to the holding of data and instructions in the computer's main memory, for manipulations.

Processing:- 

Refers to performing operations ( both arithmetic and logical ) or manipulation of data entered into the computer so that useful information may be take out of the entered data. 

Outputting:- 

Refers to the process of showing the information or result to the user either on screen ( monitor ) or on paper ( through printer). 

Controlling:-

Refers to directing all the above processes, in coordination. This controlling is done by the Control Unit (CU) in a CPU. 

The CPU of a small computer has a single microprocessor.

A microprocessor contains a control unit and an Arithmetic and Logic Unit (ALU). When main memory is added to a microprocessor, It becomes a CPU. 

The major sections of a CPU are.

1. Primary Memory 
2. ALU ( Arithmetic and Logic Unit )
3. Control Unit ( CU )