The generations are based on technologies used in computer. There are Six generation of computer.
| Sr. No | Generations | Technology | Duration |
| 1 | First Generation | Vacuum Tube | 1942-1955 |
| 2 | Second Generation | Transistor | 1955-1964 |
| 3 | Third Generation | Integrated Circuit(IC) | 1964-1975 |
| 4 | Fourth Generation | Microprocessor | 1975-2010 |
| 5 | Fifth Generation | Artificial Intelligence | 2010- Present |
| 6 | Sixth Generation | Quantum Computing | Future Generation |
First Generation Computers-Vacuum Tube-(1942-1955):
In this period computer components used the vacuum tube for the amplification of electronic signals. The vacuum tube was the latest technology at that time for this purpose. These vacuum tube computers are referred to as first generation computer. The examples of first generation computer are ENIVAC and UNIVAC-I.
Features:
- Large in Size
High energy consumption- More heat emission
- Air -conditioning required
- Less accurate
- Less reliable
- Slow in speed
- Limited storage
- Costly
- Non-portable
- Difficult to program
- Special purpose computer.
High energy consumption
Second Generation Computers-Transistor-(1955-1964):
In 1947, the electronic engineers include John Bardeen, William Brattain and William Shockley invented the TRANSISTOR that was more reliable, more accurate, and smaller than vacuum tube. In 1955, the engineers started to use the transistors in manufacturing components instead of vacuum tubes. The examples of second generation computers are IBM 1400 series, IBM 7094 series, IBM 1400 series and CDC 164 etc.
Features:
- Fastest of their age
- Small in size as compared to the first generation computers
- Less energy consumption
- Less heat emission
- Air –conditioning required
- More accurate
- More reliable
- Less costly
- Better Portable
- Used assembly language to program
- Wider Commercial use
Third Generation Computers-Integrated Circuit-(1964-1975):
Advances in electronics technology continued and the advent of “microelectronics” technology made it possible to integrate large number of circuit elements into very small(less than 5 mm square) surface of silicon known as “chips”. This new technology was called “integrated circuits” (ICs).A single IC chip may contain thousands of transistors.
Jack kilby developed the idea of integrated circuit in 1958.
The examples of third-generation computers are IBM system/360, IBM 370, UNIVAC 1108 and UNIVAC 9000 etc.
Features:
- Fastest of their age.
- Small in size and easily portable
- Very low energy consumption
- Very low heat emission, so less need of air conditioning required
- More reliable
- More accurate
- Very low cast
- Used high level language for programming.
- Commercial production was easier and cheaper
Small in size and easily portable
Fourth Generation Computers-Microprocessor-(1975-2010):
A fourth generation computer, which is what we have now, has Microprocessor (Chip) as its brain. It is LSI (Large scale Integration), VLSI (Very Large Scale Integration) and ULSI (Ultra Large Scale Integration) circuit technology which led to the development of very small but extremely powerful computers.
In 1971, Ted Hoff produced the first microprocessor for Intel. It was known as Intel 4004. Microprocessor is used in many electronic devices like barcode reader, optical reader, and laser printer etc. The examples of fourth generation computers a
re IBM PC and Apple Macintosh. These computers are based on the best technology and are most beneficial of today.
Features:
- Fastest of today
- Very small in size and easily portable
- Nominal energy consumption
- No heat emission and no air conditioning require.
- Most accurate
- Most reliable
- Cheapest among all generations
- Used 4G language to program
- Maximum commercial use
Fifth Generation Computers-Artificial Intelligence – (2010 to Present):
Scientists are now at work on the fifth generation computers-a dream, but not yet a reality. They aim to bring us machines is based on Artificial Intelligence (AI).AI used to develop machines with human-like qualities such as learning, seeing and hearing etc. In nature, it will not do just data processing but knowledge processing. The technologies which are used to develop these machines include quantum computation, molecular technology and nano technology.
Features:
Scientists are trying to create the following capabilities in computer.
- Its own decision power
- See and copy (learn) rather than installation of software.
- Extra high processing power
- Extra-large storage capacity.
Sixth Generation Computers-Quantum Computers – (Future Generation):
till 2021 most of us consider fifth generation devices are under development process like AI which has completed its development for all considering technologies. but one step more forward to future generation on that Scientists are considering and promising known as Quantum Computers.
