COMPUTER - GENERATIONS
Computer Generations
Generation in computer terminology is a change in technology a computer
is/was being used. Initially, the generation term was used to distinguish
between varying hardware technologies. But nowadays, generation includes
both hardware and software, which together make up an entire computer
system.
There are totally five computer generations known till date. Each generation
has been discussed in detail along with their time period, characteristics.
We've used approximate dates against each generations which are normally
accepted.
FOLLOWING ARE THE MAIN FIVE GENERATIONS OF COMPUTERS:
S.N. Generation & Description
First
Generation
The period of first generation: 1946-1959. Vacuum tube based.
Second
Generation
The period of second generation: 1959-1965. Transistor based.
Third
Generation
The period of third generation: 1965-1971. Integrated Circuit based.
Fourth
Generation
The period of fourth generation: 1971-1980. VLSI microprocessor based.
Fifth
The period of fifth generation: 1980-onwards. ULSI microprocessor based
Generation
First Generation
The period of first generation was 1946-1959.
First generation of computers started with using vacuum tubes as the basic
components for memory and circuitry for CPU (Central Processing Unit).
These tubes like electric bulbs produced a lot of heat and were prone to
frequent fusing of the installations, therefore, were very expensive and could
be afforded only by very large organisations.
In this generation, mainly batch processing operating systems were used. In
this generation, Punched cards, Paper tape, Magnetic tape Input & Output
device were used.
There were machine codes and electric wired board languages used.
The main features of First Generation are:
Vacuum tube technology
Unreliable
Supported Machine language only
Very costly
Generate lot of heat
Slow Input/Output device
Huge size
Need of A.C.
Non-portable
Consumed lot of electricity
Some computers of this generation were:
ENIAC
EDVAC
UNIVAC
IBM-701
IBM-650
Second Generation
The period of second generation was 1959-1965.
This generation using the transistor were cheaper, consumed less power, more
compact in size, more reliable and faster than the first generation machines
made of vacuum tubes. In this generation, magnetic cores were used as
primary memory and magnetic tape and magnetic disks as secondary storage
devices.
In this generation, assembly language and high-level programming language
like FORTRAN, COBOL were used.
There were Batch processing and Multiprogramming Operating system used.
The main features of Second Generation are:
Use of transistors
Reliable as compared to First generation computers
Smaller size as compared to First generation computers
Generate less heat as compared to First generation computers
Consumed less electricity as compared to First generation computers
Faster than first generation computers
Still very costly
A.C. needed
Support machine and assembly languages
Some computers of this generation were:
IBM 1620
IBM 7094
CDC 1604
CDC 3600
UNIVAC 1108
Third Generation
The period of third generation was 1965-1971.
The third generation of computer is marked by the use of Integrated Circuits
(IC's) in place of transistors. A single IC has many transistors, resistors and
capacitors along with the associated circuitry. The IC was invented by Jack
Kilby. This development made computers smaller in size, reliable and
efficient.
In this generation, Remote processing, Time-sharing, Real-time, Multiprogramming Operating System were used.
High-level language (FORTRAN-II TO IV, COBOL, PASCAL PL/1, BASIC,
ALGOL-68, etc.) were used during this generation.
The main features of Third Generation are:
IC used
More reliable
Smaller size
Generate less heat
Faster
Lesser maintenance
Still costly
A.C. needed
Consumed lesser electricity
Support high-level language
Some computers of this generation were:
IBM-360 series
Honeywell-6000 series
PDP(Personal Data Processor)
IBM-370/168
TDC-316
FOURTH GENERATION
The period of Fourth Generation was 1971-1980.
The fourth generation of computers is marked by the use of Very Large Scale
Integrated (VLSI) circuits. VLSI circuits having about 5000 transistors and
other circuit elements and their associated circuits on a single chip made it
possible to have microcomputers of fourth generation. Fourth Generation
computers became more powerful, compact, reliable, and affordable. As a
result, it gave rise to personal computer (PC) revolution.
In this generation, Time sharing, Real time, Networks, Distributed Operating
System were used.
All the higher level languages like C and C++, DBASE, etc., were used in this
generation.
The main features of Fourth Generation are:
VLSI technology used
Very cheap
Portable and reliable
Use of PC's
Very small size
Pipeline processing
No A.C. needed
Concept of internet was introduced
Great developments in the fields of networks
Computers became easily available
Some computers of this generation were:
DEC 10
STAR 1000
PDP 11
CRAY-1 (Super Computer)
CRAY-X-MP (Super Computer)
FIFTH GENERATION
The period of Fifth Generation is 1980-till date.
In the fifth generation, the VLSI technology became ULSI (Ultra Large Scale
Integration) technology, resulting in the production of microprocessor chips
having ten million electronic components.
This generation is based on parallel processing hardware and AI (Artificial
Intelligence) software.
AI is an emerging branch in computer science which interprets means and
methods of making computers think like human beings.
All the higher level languages like C and C++, Java, .Net, etc., are used in this
generation.
AI includes:
Robotics
Neural networks
Game Playing
Development of expert systems to make decisions in real life situations.
Natural language understanding and generation.
The main features of Fifth Generation are:
ULSI technology
Development of true artificial intelligence
Development of Natural language processing
Advancement in Parallel Processing
Advancement in Superconductor technology
More user friendly interfaces with multimedia features
Availability of very powerful and compact computers at cheaper rates
Some computers types of this generation are:
Desktop
Laptop
NoteBook
UltraBook
Computers can be broadly classified by their speed and computing
power.
Sr.
No.
Type
PC (Personal Computer)
WorkStation
Mini Computer
Specifications
Single
user
computer
system.
Moderately
powerful
microprocessor.
Single user computer system. Similar to Personal Computer but
have more powerful microprocessor.
Multi-user computer system. Capable of supporting hundreds of
users simultaneously.
Multi-user computer system. Capable of supporting hundreds of
Main Frame
users simultaneously. Software technology is different from
minicomputer.
Supercomputer
An extremely fast computer, which can perform hundreds of
millions of instructions per second.
PC (Personal Computer)
A PC can be defined as a small, relatively inexpensive computer
designed for an individual user. PCs are based on the microprocessor
technology that enables manufacturers to put an entire CPU on one
chip. Businesses use personal computers for word processing,
accounting, desktop publishing, and for running spreadsheet and
database management applications. At home, the most popular use for
personal computers is for playing games and surfing the Internet.
Although personal computers are designed as single-user systems, these
systems are normally linked together to form a network. In terms of
power, nowadays high-end models of the Macintosh and PC offer the
same computing power and graphics capability as low-end workstations
by Sun Microsystems, Hewlett-Packard, and DELL.
WORKSTATION
Workstation is a computer used for engineering applications
(CAD/CAM), desktop publishing, software development, and other
such types of applications, which require a moderate amount of
computing power and relatively high quality graphics capabilities.
Workstations generally come with a large, high-resolution graphics
screen, large amount of RAM, inbuilt network support, and a graphical
user interface. Most workstations also have a mass storage device such
as a disk drive, but a special type of workstation, called a diskless
workstation, comes without a disk drive.
Common operating systems for workstations are UNIX and Windows
NT. Like PC, Workstations are also single-user computers. However,
workstations are typically linked together to form a local-area network,
although they can also be used as stand-alone systems.
