There are five generations of the computer, which can be classified as below:
1. First Generation (1946 - 1959): During the first generation, computers were based on
electronic valves (Vacuum Tubes).
Vacuum Tube Technology
Unreliable
Supported Machine Language only
Very costly
Generated lot of heat
Slow input and output device
Huge in size
Need of A.C.
Non-portable
Consumed lot of electricity
Computers of 1st generation-
ENIAC
EDVAC
UNIVAC
IBM-701
IBM-650
2. Second Generation (1959 - 1965): During the second generation, computers were
based on Transistors.
Use of Transistor
Reliable in comparison of first generation computer
Smaller size as compared to first generation computer
Generated less heat as compared to first generation computer
Consumed less heat as compared to first generation computer
Faster than first generation computer
Still very costly
Need of A.C.
Supported Machine Language only
Computers of 2nd generation-
IBM-1620
IBM-7092
CDC-1604
CDC-3600
UNIVAC-1108
3. Third Generation (1965 - 1971): During the third generation, computers were based
on Integrated Circuits (ICs).
IC used
More reliable in comparison to previous two generations
Smaller in size
Generated less heat
Faster
Lesser maintenance
Still costly
A.C. needed
Consumed lesser electricity
Supported high-level language
Computers of 3rd generation-
IBM-360 Series
Honeywell-6000 Series
PDP(Personal Data Processor)
IBM-370/168
TDC-316
4. Fourth Generation (1971 - 1980): During the fourth generation, computers were
based on very large scale integrated (VLSI) circuits.
VLSI Technology used
Very cheap
Portable and Reliable
Use of PC’s
Very small in size
Pipeline processing
No A.C. Needed
Concept of internet was introduced
Great developments in the fields of networks
Computers became easily available
Computers of 4th Generation-
DEC-10
STAR-1000
PDP-11
CRAY-1(Super Computer)
CRAY-X-MP(Super Computer)
5. Fifth Generation (1980 - Present): The fifth generation is still ongoing. The computers
are based on multiple technologies, such as ultra large scale integration (ULSI),
artificial intelligence (AI), and parallel processing hardware. AI includes:
Robotics
Neural Networks
Game playing
Development of Expert Systems to make decisions in real life situations
Natural language understanding and generation.
Main Features-
ULSI Technology
Development of true Artificial Intelligence
Development of natural language processing
Advancement in parallel processing
Advancement in super-conductor technology
More user friendly interfaces with multimedia features
Availability of very powerful and compact computers at cheaper rates.
Computers of 5th generation-
Desktop
Laptop
Notebook
Ultrabook
Chromebook
