Various Parts of Computer

Introduction:

A computer is a machine that processes facts and figures to produce useful information. Since 1940s people began using computers to solve their problems, mainly involving mathematical equations or working with numerical calculations. The routine calculations were done by the computers. Over the years computers have become smaller, more powerful and less expensive. More and more organizations are using computers and more and more people are required to learn computer skills.

The computer is a powerful tool which, if properly directed and used, can extend the capability of operations and management of organizations.

Computers are widely used in business, health care, education, science , archeology, engineering, architecture, manufacturing , weather forecasting, law enforcement, government, military, music, films and at home. Understanding computers and how to use them is vital both now and in future.

5 Generations of computers:

The electronic digital computers, which were introduced in 1950s were using vacuum tubes. Following this, the development in the electronic components helped in the development of digital computers also. The second – generation computers used transistors.

The introduction of integrated circuits(ICs), also known as chips opened the door for the development of third generation computers. A very large number of circuit elements(transistors, diodes, resistors, etc.,) could be integrated into a very small (less than 5mm square) surface of silicon and hence the name IC. The third generation computers used small – scale integrated circuits(SSI) which contain about 10-20 components. When large – scale integrated circuits (LSI) (around 30,000 components) were developed, the fourth generation computers were produced.

Basic units of a computer:

A computer is designed using three basic units. They are,

• Input unit:   computers need to receive data and instructions in order to solve any problem. Therefore, we need to put the data and instructions into the computer. The input unit consists of one or more input devices. The keyboard and mouse of a computer are the most commonly used input devices.
• Central processing unit(cpu):   It is the main part of computer system like the heart of a human being. It interprets the instructions in the program and executes one by one. It consists of three major units.
  • Control unit:  It controls and directs the transfer of program instructions and data between various units.
  • Arithmetic and logic unit(ALU): Arithmetic operations like addition(+), subtraction(-), etc., and logical operations like  comparisons using the operators < , > , <= , >= etc., are being carried out in this unit.
  • Memory unit(MU):   It is used to store the programs and data.
• Output unit:  It is used to print / display the results, which are stored in the memory unit.