Generation of Computer

Generations of Computer:

                   The term computer generation is refered as a major development in electronic data processing. The evolution of computer passed different stages. The development of computers from 1943 A.D. to today are classified into five periods. The development of computers that took place in each time period is "Generation of Computer". In each generation , there are always something new in technology, the computers became smaller, cheaper, more powerful, more efficient and reliable than the old generation of computers.

First(1st ) Generation Computers:

                     The first(1st) generation computers developed during 1946 AD to 1958 AD. The main components of first(1st) generation were vacuum tubes. These computers used to be huge in size, very slow , low capacity, very expensive, very difficult to operate, unreliable and required regular repairing & maintenance. Besides this they need a lot of power an& produced huge amount  of heat. Machine language was used for writing the programs. These computers were used only for science and engineering applications. Some examples are ENIAC, EDSAC, UNIVAC, EDVAC, BIZMAC, etc.

Main features of first generation computers:

1. Valves and vacuum tubes were used as electronic circuit, magnetic drum for primary storage and memory delay lines for memory.
2. They consumed a lot of power and produced a lot of heat.
3. Machine language was used for writing the programs which was tedious and time consuming.
4. They were used only for science and engineering applications.  

Second Generation Computers:

             The second generation computers were developed during 1959 AD to 1964 AD. They used transistors as the main electronic component. Due to the transistors the second generation computers became more powerful, smaller, reliable, faster and less expensive than the first generation computers. UNIVAC-I, IBM-700, IBM-1401, NCR-300, etc are the second generation computers.

Some features of Second generation computers are :

1. They used transistor as the main electronic component.
2. They were smaller, faster, less expensive and more reliable than the first generation computers.
3. Punched cards were used for input and printouts for output.
4. They consumed less electric power than the first generation computers.
5. Assembly language and high level language could be used in the second generation computer.
6. They had more storage capacity.

Third Generation Computers:

              The main component of third generation computer was integrated circuit(IC). The manufacturer used solid state technology technique in which a number of transistors were put on to one silicon chip. Its size was about half an inch. It was called IC. These computers were more reliable, smaller, faster, easier to operate, less expensive, high capacity than previous generation computers. Low level language and high level languages like Basic, FORTRAN including RPG (Report Program Generator) were used for writing programs. Semiconductor memories were invented for data storage. Besides this, the batch operating system were also developed. They were used in both scientific and business applications. Some examples of third generation computers are IBM 360, ICL 2800, IBM 370, General Electronic 265, Burroughs 5700, CDC 3000, Digital Equipment PDP-8 Series, etc.

Some features of third generation computers are:

1. They used ICs as the main electronic component.
2. They were smaller, faster, less expensive and more reliable than the second generation computers.
3. They consumed less electric power than the previous generation of computers.
4. They used  keyboards and monitors for the input and output of data.
5. They used operating system so they were capable of running different programs.
6. They used semiconductor memory for internal storage.

Fourth Generation Computers:

             The developments of fourth generation computers were started from 1975 AD. The computers that are being used nowadays belong to the fourth generation. The fourth generation computers are based on microprocessor. The first microprocessor Intel 4004 was developed in 1971 by American  Intel Corporation. The fourth generation computers are smaller, cheaper, faster, more efficient , more capable and more reliable than third generation computers. IBM PCs, IBM compatible PCs, Apples PCs, etc, are the fourth generation computers.

Some features of fourth generation computers are:

1. They used LSI (Large Scale Integration) and VLSI (Very Large Scale Integration) as the main electronic component.
2. They are smaller, faster, less expensive and more reliable than the third generation computers.
3. They have large amount of internal and external storage.
4. They have capable of performing varieties of tasks.
5. They use advanced input and output devices like optical reader , scanner, DVD drive, plotter, speaker, etc. 

Fifth Generation Computers:

            In the fifth generation, lots of researches are going on. The major shortcomings in the earlier generation computers was lack of thinking power. These computers combine hardware & software to produce Artificial Intelligence (AI) and will be able to understand natural languages. They will be using Ultra Large Scale Integration (ULSI) and having super conductors using Gallium Arsenide(GA) or bio chips. Expert systems are the important aspects of the fifth generation. Examples are Caduceus and Prospector. Automatic programmings, computational logics, pattern recognitions will be extensively used in near future with development of artificial intelligence.

Main features of Fifth generation computers are: 

1. These computers will use ULSI and have super conductors using Gallium Arsenide or biochips.
2. They will be able to understand natural languages and will have artificial intelligence.
3. Automatic programmings, computational logics, patterns recognitions will be extensively used.