Generations of Computer
The development, in computers hardware and software, since the invention of first electro-mechanical, has been categorized in the following generations.
(1) First Generation (1942-1955)
The first generation was started 1942 with the invention of Mark-I computer. Computer in this age were based on vacuum tube technology. Hundreds and thousands vacuum tubes made the size of computer very large. Besides that the tubes emitted tremendous heat and caused in breaking of the tubes and replacing them frequently. Despite these drawbacks, these computers made a smooth pavement towards structure of computer.
(2) Second Generation (1955-1964)
In second generation vacuum tube were replaced by transistor technology. Transistors were smaller in size that’s why it reduced the size of computer and also the cost reduced upto a reasonable level. Computer in this age were able to calculate data in milliseconds.
Beyond the many advantages, still there were some problems with size, cost, and air conditioning environment of computers. UNIVAC-II, EDVAC, IBM-1401 are the famous computers of that age.
(3) Third Generation (1965-1975)
Computers in this period were based on integrated circuits (I.C). The development of I.C is the result of solid state technology. Thus the size of computer shrank more then the previous systems. I.C is basically the collection of many electronic circuits on a single silicon chip. These computers consumed a less amount of energy, produced less heat. Also they were capable of using High-level languages. But still Air-conditioning and High technology for I.C were required.
(4) Fourth Generation (1975-1980)
Fourth Generation is the most enormous generation because it yielded “Microprocessor” which possesses thousands I.Cs at a single ship. Thus the size of computer was limited only to the top of a table. Micro computers or personal computer were introduced commercially in this period.
Computers at Fourth generation were smaller in size, cost heat and electric consumption. Their speed was much more then that of previous. Now, computers were not special purpose but they were general-purpose.
For Example: IBM-PC.
(5) Fifth Generation (1980-Present)
Fight generation mainly focuses on software developments much more work is conducted in the field of artificial Intelligence (A.1) Robotics, Natural Languages processing (NLP).
The engineers concentration was mainly focused on the idea to make computer think, analyze and generation inferences. Also, computer should behave like Human Experts like Doctors, Engineers, Teachers translators, Psychologists, ect. As a result much more experience and work is put to operation.
Still there is much work expected to be conducted in the field of ANN or Artificial Neural Network. In this way computer would be able to respond to physical changes in environment and expose good results of like that of Human.