THE FIVE GENERATION OF COMPUTER.

FIRST GENERATION (1940-1956) VACUUM TUBES

During the period of 1940 to 1956 first generation of computers were developed. The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms.

The vacuum tube was developed by Lee De Forest. A vacuum tube is a device generally used to amplify a signal by controlling the movement of electrons in an evacuated space. They were very expensive to operate and in addition to using a great deal of electricity, generated a lot of heat, which was often the cause of malfunctions.

First generation computers relied on machine language, the lowest-level programming language understood by computers, to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts.

The UNIVAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC was the first commercial computer delivered to a business client, the U.S. Census Bureau in 1951.

CHARACTERISTICS
1) First generation computers were based on vacuum tubes.
2) The operating systems of the first generation computers were very slow.
3) They were very large in size.
4) Production of the heat was in large amount in first generation computers.
5) Machine language was used for programming.
6) First generation computers were unreliable.
7) They were difficult to program and use.
UNIVAC, EDVAC, EDSAC and ENIAC computers are examples of first generation computing devices.

SECOND GENERATION (1956-1963) TRANSISTORS

During the period of 1956 to 1963 second generation of computers were developed. The second generation computers emerged with development of Transistors.

The transistor was invented in 1947 by three scientists J. Bardeen, H.W. Brattain and W. Shockley. A transistor is a small device made up of semiconductor material like germanium and silicon. Even though the Transistor were developed in 1947 but was not widely used until the end of 50s. The transistor made the second generation computers faster, smaller, cheaper, more energy-efficient and more reliable than their first-generation computers. Even though the transistor used in the computer generated enormous amount of heat which ultimately would lead to the damage of the computers but was far better than vacuum tubes. Transistors replaced vacuum tubes and ushered in the second generation of computers. Second-generation computers still relied on punched cards for input and printouts for output. Second generation computers used the low level language i.e. machine level language and assembly language which made the programmers easier to specify the instructions. Later on High level language programming were introduced such as COBOL and FORTRAN. Magnetic core was used as primary storage. Second generation computer has faster input /output devices which thus brought improvement in the computer.

CHARACTERISTICS

1) Transistors were used in place of vacuum tubes.
2) Second generation computers were smaller in comparison with the first generation computers.
3) They were faster in comparison with the first generation computers.
4) They generated less heat and were less prone to failure.
5) They took comparatively less computational time.
6) Assembly language was used for programming.
7) Second generation computers has faster input/output devices.

IBM 7000, NCR 304, IBM 650, IBM 1401, ATLAS and Mark III are the examples of second generation computers.

THIRD GENERATION (1964-1971) INTEGRATED CIRCUITS

The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers.

Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program

that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors.

CHARACTERISTICS
1) IC was used instead of transistors in the third generation computers.
2) Third generation computers were smaller in size and cheaper as compare to the second generation computers.
3) They were fast and more reliable.
4) High level language was developed.
5) Magnetic core and solid states as main storage.
6) They were able to reduce computational time and had low maintenance cost.
7) Input / Output devices became more sophisticated.

PDP-8, PDP-11, ICL 2900, IBM 360 and IBM 370 are the examples of third generation computers.

FOURTH GENERATION (1971-PRESENT) MICROPROCESSORS

The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer—from the central processing unit and memory to input/output controls—on a single chip.

In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the Macintosh. Microprocessors also moved out of the realm of desktop computers and into many areas of life as more and more everyday products began to use microprocessors.

As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.  

CHARACTERISTICS
1) The fourth generation computers have microprocessor-based systems.
2) They are the cheapest among all the computer generation.
3) The speed, accuracy and reliability of the computers were improved in fourth generation computers.
4) Many high-level languages were developed in the fourth generation such as COBOL, FORTRAN, BASIC, PASCAL and C language.
5) A Further refinement of input/output devices was developed.
6) Networking between the systems was developed.

IBM 4341, DEC 10, STAR 1000, PUP 11 and APPLE II are the examples of fourth generation computers.

FIFTH GENERATION (PRESENT AND BEYOND) ARTIFICIAL INTELLIGENCE

Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today.

The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.

CHARACTERISTICS
1) The fifth generation computers will use super large scale integrated chips.
2) They will have artificial intelligence.
3) They will be able to recognize image and graphs.
4) Fifth generation computer aims to be able to solve highly complex problem including decision making logical reasoning.
5) They will be able to use more than one CPU for faster processing speed.
6) Fifth generation computers are intended to work with natural language.