Generation is a computer
terminology which means change in technology of computer being used. Initially,
it meant change in the technology of hardware but now it also includes change
in technology of software which together makes up an entire computer system
There are total five
generations of computer known till date each discussion has been discussed in
detail along with its time period.
Following are the five
generation of computers
1) First Generation Computers
The period of first
generation computers was from 1946 to 1959. They used vacuum tubes as a basic
component of memory and circuitry for central processing unit (CPU). These
tubes were very expensive. They required a lot of electricity and they
generated a lot of heat. Therefore, they required a large cooling down system
made from air conditioners. They were unreliable. This generation computers
required continuous replacement of tubes. In this generation mainly batch
processing system were used. Punch card, paper tape and magnetic tape were used
as input and output devices. They used machine language only. Their sizes were
huge and they were non-portable. They were used for only scientific purposes.
They run only scientific applications. They were used only at commercial level
and only high level organization could afford them. They were very costly. They
were difficult to use.
SOME REPRESENTATIVE SYSTEMS
·
EDVAC
·
EDSAC
·
UNIVAC I
·
IBM 701
2) Second Generation Computer
The period of second
generation computers was from 1959 to 1965. In this generation transistors were
used which were cheaper than vacuum tubes. 240 transistors were used instead of
one vacuum tube. They consumed less power than first generation computers.
They
were used at commercial level only. They
were more compact in size. They were still very costly. They were more reliable
and faster than first generation computers made of vacuum tubes. In this
generation computers magnetic cores were used as primary memory and magnetic
disks were used as secondary memory. In this generation assembly language and high
level languages such as FORTRAN and COBOL were used. They used batch processing
operating systems.
Some
Representative Systems
·
IBM-1620
·
IBM-7094
·
CDC-1604
·
CDC-3600
·
UNIVAC-1108
3) Third Generation computer
The period of third
generation was from 1965 to 1971. The major invention in the third generation
computer was the development of integrated circuits (IC’s). A single IC chip
contained thousands of transistors, resistors and capacitors. They used IC’s
with MSI (Medium Scale Integration) technology. These
computers were smaller in size than the first and second generation computers.
They were faster than first and second generation computers. They were less
expensive and consumed less energy. They were reliable and portable. It was
user-friendly and easy to upgrade. They became very common in medium to large
scale business. These computers used magnetic core memory as internal storage.
Larger capacity disks and magnetic tapes were used as secondary storage
devices. These computers used keyboards and monitors. They were multitasking.
They used multi-processing, multi-programming and time sharing operating
systems. High-level languages
(FORTRAN-II TO IV, COBOL, PASCAL PL/1, BASIC, ALGOL-68 etc.) were used during
this generation.
Some
Representative Systems
·
IBM-360
·
DEC
·
PDP-8
·
UNIVAC-1108
·
UNIVAC-9000
·
IBM-370
4) Fourth Generation
Computer
The period of this computer generation was from 1971 to 1980.
They were smaller than first, second and third generation computers. They were affordable,
reliable and easy to use PC’s. They were more powerful than first, second and
third generation computers. At that time they were called as super computers.
They were totally general purpose machines. They were easier to produce
commercially and easier to upgrade than first, second and third generation
computers. In these computers rapid software development was also possible. Fourth
generation of computers started with the invention of microprocessor. It
revolutionized the computer world. Advancements were made in IC’s technology.
LSI (large scale integrated) circuits and VLSI (very large scale integrated) circuits
were designed which contributed towards the invention of microprocessors, which
made it possible to make micro-computers. Computer of this generation used
semi-conductor memory which increased the internal storage of the computers.
These computers had high processing speed. All the high-level languages like C,
C++, DBASE etc., were used in this generation. Operating systems for PC’s with
graphical user inter phase were made and multiple windows on a single terminal
screen was possible.
Some
Representative Systems
·
DEC
10
·
STAR
1000
·
PDP
11
·
PDP
8
·
IBM
360/370
5) Fifth Generation
Computers
The period of fifth
generation computers is from 1980 till now. These computers are portable,
cheaper, reliable and more powerful. They are easy to use and rapid software
development is possible. They are totally general purpose. In this generation
VLSI circuits became ULSI (ultra large scale integrated) circuits which made it
possible to make microprocessors having ten million components on single chip. Fifth
generation computing devices, based on artificial intelligence (AI), are still
in development stage. Though there are some applications, such as voice
recognition, that are being used today. The use of parallel processing and
super conductors is helping to make AI a reality. AI is an emerging branch in
computer science, which interprets means and methods to make computer think
like a human being. It uses all high level languages like C++ and JAVA. Quantum
computation, molecular and Nano-technology will radically change the face of
computers in future. The goal of fifth generation computing is to develop such
devices that will be able to respond to natural language input and capable of
learning and self-organization.
Some
Representative Systems
·
IBM
notebooks
·
Pentium
PC’s
·
Laptop
·
Ultra
book
·
Tablets
