History Of Computers

Computers
Computers are the
Electronic Device
Have Storing Capabilities
Have Processing Capabilities
Give outputs against inputs
Give instructions to carry out operations and then store in memories Computers made our lives easy and reliable. Now a day, computer becomes necessary for us to survive in this modern globe

Advantages
Disadvantages
fast communication
health problems
reliability
security problems
consistency
violation of privacy
storage
impact on labor force
highly accurate
impact on environment

History of computers
Computers were invented because “necessity is the mother of invention”. Man always searched for a fast calculating device. It took long time to invent the digital computers. A brief history behind the invention of computer is as follows:

Abacus:
It was a wooden rack had horizontal wires with beads strung on them Abacus was the first computing device
It was developed 5000 years ago
It was used to perform simple addition and subtraction

John Napier’s Bone:
He was a Scottish mathematician. He created logarithm tables to carry out calculations. He also created a device called Napier’s bones. It has rods to perform arithmetic calculations The device was widely used by accountants and bookkeepers

Blaise Pascal:
He was a French mathematician, invented a mechanical adding machine in 1642 known as Pascline Calculator Machine contained metal wheels. Each wheel displayed the digit 0 to 9 Only could do was add and subtract numbers

Von Leibnitz:
He was a German scientist. He developed a calculating machine in 1694 It was the calculator that could multiply and divide
It was more reliable and accurate as compared with Pascal’s calculator

Charles Xavier:
A French scientist who developed a machine which could perform addition, subtraction, multiplication and division

Punched Board:
A French engineer Joseph developed punchboard system for power looms It was used to create weaving patterns on cloths. Later on, the system was used computing devices

Charles Babbage:
He invented a analytical engine in 1842 that was automatic
This engine could perform 60 additions per minute

Herman Hollerith:
In 1889, Herman applied the idea of punchboards in computers He used punch cards for input and output

Atanasoff:
He was a professor at IOWA University
He invented electronic computer
He applied Boolean algebra to computer circuitry

George Boole
He simplified binary system of algebra.
His rule states that any mathematical equation can be stated simply as either true or false.

Different well known early computers are as follows
The mark I computer(1937-1944)
The ENIAC(1943-1946)
The EDVAC(1946-1952)
The UNIVAC(1951-)
Generation of Computers
The development of electronic computers can be divided into generations depending upon the technologies used. Different generation of computer is as follows:

1st Generation
Vacuum Tube
1942-1955
2nd Generation
Transistors
1955-1964
3rd Generation
Integrated Circuits
1964-1975
4th Generation
Microprocessor
1975-Present
5th Generation
AI – Artificial Intelligence
Present and Beyond

1st Generation Computers
The beginning of commercial computer age is from UNIVAC.
It was developed by two scientists Mauchly and Echert at the census department of US in 1947 The First generation computers were used during 1942 – 1955 Examples of First generation computers are ENIVAC and UNIVAC I Advantages:

Vacuum tubes were the only electronic component available during those days Vacuum tube technology made possible to make electronic digital computers The computers could calculate data in millisecond

Disadvantages
These computers were very large in size
Consumed a large amount of energy
They heated very soon due to thousands of vacuum tubes
They were not very reliable
Constant maintenance was required
Non portable
Costly commercial production  limited commercial use
Very slow speed
Limited programming capabilities
Used machine language only
Use magnetic drums which provide very less data storage

2nd Generation Computers
Second Generation Computers used transistors. Scientist of bell laboratories developed transistors in 1947. These scientists include john Bardeen, William Brattain and William Shockley. The size of computer was decreased by replacing vacuum tubes with transistors. Examples are IBM 7094 Series, IBM 1400 Series and CDC 164 etc Advantages

Smaller in size
More reliable
Use less energy and were not heated
Wider commercial use
Better portability
Better speed and could calculate data in micro seconds
Used assembly language instead of machine language
Disadvantages
Air conditioning was required
Constant maintenance was required
Commercial production was difficult
Only used for specific purposes
Costly and not versatile
Punch cards were used for inputs

3rd Generation Computers
These computers used the integrated circuits (IC)
Jack Kilby developed the concept of IC in 1958
The first IC was invented and used in 1961
The size of an IC is about ¼ square inch
A single IC chip may contain thousand of transistors
The computers became smaller in size, faster, more reliable and less expensive Examples are IBM 370, IBM System/360, UNIVAC 1108 and UNIVAC 9000 etc Advantages
Smaller in size as compare to previous generations
More reliable
Used less energy
Produced less heat as compared to previous generation computers Better speed and could calculate data in nano seconds
Used fan for heat discharge to prevent damage
Totally general purpose
Could be used for high level languages
Good storage
Less expensive
Used mouse and keyboard for input
Disadvantages
Air conditioning was required
Highly sophisticated technology required for the manufacturing of IC chips

4th Generation Computers
These computers started with the inventions of micro processors The microprocessors contain thousands of IC’s
Ted Hoffs produced the first micro processors in 1971 for Intel It was known as Intel 4004
The technology of IC’s improved rapidly
The LSI circuit and VLSI circuit were designed. It greatly reduced the size of computers The size of modern microprocessors is usually 1 square inch. It contains millions of electronic circuits Examples are Apple Macintosh, and IBM PC

Advantages
More powerful and reliable than previous generations
Very small size
Less power consumption and less heat generated
Fan for heat discharging
No air conditioning is required
Best speed to read instructions i.ie. 1 billionth per second Totally general purpose
Less need of repairing
Cheapest among all generations
All types if high level languages can be used in this type of computers Disadvantages
The latest technology is required for manufacturing microprocessors

5th Generation Computers
Scientists are now working on Fifth Generation Computers using recent engineering advances. It is based on the technique of artificial intelligence (AI). Computer can understand spoken words and imitate human reasoning. Scientists are working to increase the speed of the computer. They are trying to create computer with real IQ with the help of advanced programming and technologies. The advancement in modern technologies will revolutionize the computer in future.