The development of modern computers took place into five distinct phases on the basis of main component, the size, processing speed, cost, memory capacity etc used by them are known as generation of computer. Each generation computer is made improvements over the previous generations in terms of technology. The improvement in technology resulted in computer lower cost, high speed, and smaller size, greater memory capacity and more reliable. There are five generations of computer. They are:
- First Generation Computer
- Second Generation Computer
- Third Generation Computer
- Fourth Generation Computer
- Fifth Generation Computer
Technologies used in different generation of computer are described below.
Vacuum tube is used in first generation of computers. A vacuum tube is a device that controls electric current between electrodes in an evacuated container. It has contains positive electrode and a negative electrode. Vacuum tubes were also used in radios, televisions, radar equipment etc.
Transistor is used in Second generation of computers. A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor’s terminals controls the current through another pair of terminals. The transistor is the fundamental building block of modern electronic devices. Transistor was smaller than vacuum tubes and consumed less power.
IC (Integrated Circuits)
IC is used to in third generation of computers. An integrated circuit or microchip is a set of electronic circuits on one small chip of semiconductor material, normally silicon. The integration of large numbers of tiny transistors into a small chip results in circuits that are orders of magnitude smaller , cheaper, and faster than those constructed of discrete electronic components. They have high processing speed, more reliability and low power consumption than compared to the vacuum tube and transistor.
Microprocessor is used to in fourth generation of computers. A microprocessor is a computer processor which incorporates the functions of a computer’s central processing unit (CPU) on single integrated circuit(IC). The processor is a multi-purpose, clock driven, register based, digital integrated circuit which accepts binary data as input, processes it according to the instructions stored in its memory, and provides results as output. Microprocessors contain both combinational logic and sequential digital logic. Microprocessors operate on numbers and symbols represented in the binary numeral system.
Artificial Intelligence (AI)
Fifth generation computer will use artificial intelligence and bio chip as memory device so that they can think and decide like human being. With help of Bio chips, computer will have the power of sense, logic and decision making capability. Fifth generation of computer will understand and communicate natural language with user.