Block diagram of computer

Block Diagram of Computer Explained in 5 easy steps. |

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Block Diagram of Computer Explained in 5 easy steps. |

Computer Block Diagram is a simple yet a very important factor in Computer Studies. “Computer Block Diagram” is a set of neatly organized blocks that are used for understanding the functionality of the computer. In simple words Computer Block Diagram is a figure that explains us how the computer carries out complex process.

Block Diagram of Computer

This is a complete block diagram of the computer. Here the computer is mainly divided in three parts the Central Processing Unit (CPU), Input Devices and Output Devices.

Then further the CPU is divided into two sub parts

  1. The Control Unit (CU) and
  2. The Arithmetic Logic Unit (ALU).

The Storage Unit is too divided into two parts the primary storage and the secondary storage.

All the Data that is generated by the user is stored in this Storage Unit. CPU handles the processing part of the computer. It can also be called as the “Brain” of the computer.

The central unit is responsible for all the process in the computer. The Central Unit is the one which takes the inputs from the user through input devices and displays the output of process through output devices.

Block diagram of computer

The units that are used in Computer are:

  1. Input Unit.
  2. CPU (Central Processing Unit).
  3. Storage Unit.
  4. Output Unit.

1. Input Unit:

This is the unit where the processes are initialized. It takes the inputs from the users through the input devices such as keyboard, mouse, scanners and joystick etc.

Data is stored and processed in computers in the form of binary language. So the instructions from the inputs devices are converted into binary languages in the CPU for further process.

Input devices are just a way of communicating with the computer. This the way through which real world problems are made available to the computer for processing.

Input devices are also responsible for transmitting the data to the main memory of the computer.

2. Central Processing Unit (CPU):

This is one of the most important unit in computers for processing. All the process, activities and operations are control and monitored by this unit. It has direct contact with the memory of to receive the information from the user.

When a set of instructions are received to the unit it converts those instructions into signals then those are passes to the control units.

Then those signals are then processed. Control Unit has the capability to understand those units and execute them properly and exactly.

CPU unit has 2 parts:

  • The Control Unit:

As the word “control” itself explains that it controls and monitor all the activities of the computer. This unit also has the responsibility of controlling the input/output devices for converting the instructions into binary language.

Control unit also helps in prioritizing and scheduling the tasks and processes. This unit also has the capabilities of accessing the other components of the computer for execution of the processes.

  • Arithmetic and Logic Unit (ALU):

This is the unit in computer where all processes are being processed. In this unit all the logical and athematic operators are being performed. These operations are done on the binary numbers so this is unit all together called as ALU unit.

All the outputs are based on the type and order of the inputs provided. These output change asynchronously in response to the input given at that particular instant.

This ALU unit is responsible for the logical operations like AND, OR with operations like equal to or less than and many more. This can be counted under the Logical category of the unit.

And operations like addition, multiplication, division etc. fell under the Arithmetic category of the unit.

The information required to the ALU is provided by the storage unit in those cases when operations are to done using the data.

3. Storage/Memory Unit:

This is the junction where all the required data for operations is stored. This unit can also be called as the hub of all the data. This unit is responsible for providing the data to the control unit for processes to be done.

The underlining feature is that it works in synchronized manner with the CPU. This helps in transmitting the data faster to the CPU thus resulting in faster and quick results and outputs.

This storage unit is divided into two more sub units:

  1. Primary memory.
  2. Secondary memory.
  • Primary memory:

This is a type of memory storage where the most recent memory is stored. In this memory only main and running activities are stored, it is smaller in size than secondary memory.

Data in this unit is stored temporarily and the data gets wiped out once the power is cut off, so this is also called as temporary memory or main memory.

Many of have already heard the memory type called “RAM”. So, this is also an example of primary memory.

This memory can be directly accessed by the CPU whenever needed for the processes. This memory is also used for reading and writing purposes.

If any operation is to be done on the data by the CPU, then initially that data is stored in the primary memory i.e., RAM and then processed.

  • Secondary Memory:

As the data stored in the primary memory is temporary, thus to stored permanent data secondary data is used.

For permanent data storage secondary memory is used. This provides the primary memory data with the for processing. Secondary memory is also called as auxiliary memory.

Hard disks are the examples of the secondary memory. This memory type is less expensive than the primary memory.

5. Output Unit:

This is the unit where process reaches the final stage. Output unit contains the components such as monitor, printer and projector.

The result that is obtained is from the CPU is displayed from these output devices.

There are to types of output formats:

  1. Hard Copy (Paper printed in printer).
  2. Soft Copy (Monitor).

The output devices receive binary data from the CPU and then converts it into human readable format.

Books to get more in-depth information on computer hardware.


So, this was all about Computer block diagram and its components and units. Hope you enjoyed reading the article.

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