## History of computing

Computer was invented because “necessity is the mother of invention”. Man always for a fast calculating device. It took a long time to invent the digital computer.

A brief history behind the invention of the computer is as follows:

**Abacus**

Abacus was the first computing device. It was developed 5000 years ago. It was used simple addition and subtraction. Abacus was a wooden rack. It contained horizontal wires with beads strung on them. The beads could move easily. All simple arithmetic calculations were performed by moving these beads according to programming rules.

**John Napier’s Bone**

John Napier was a Scottish mathematician. He created logarithm tables to facilitate calculations. He also created a device known as Napier’s bones. The device used rods to perform arithmetic calculations. It was designed in the early 17th century. The device was widely used by accountants and bookkeepers.

The concept of logarithm was used to develop slide rule. The modern slide rule could be used to perform arithmetic calculations. It was also used to calculate squares, square roots, logs, sine and cosine etc. The slide rule was used till the middle 70’s.

**Blaise Pascal**

Blaise Pascal was a French mathematician. He invented a mechanical adding machine in 1642 known as Pascaline Calculator. The machine contained different metal wheels. Each wheel displayed the digit 0 to 9. It could only add and subtract numbers. Division and multiplication were performed by repeated addition and subtraction. It was not a commercial success because it could not provide sufficient precision for practical use.

**Von Leibnitz**

Von Leibniz was a German scientist. He developed a calculating machine in 1694. Itwas the first calculator that could multiply and divide also. It was similar to Pascal’scalculator but it was more reliable and accurate.

**Charles Xavier**

A French scientist Charles Xavier developed a machine that could perform addition, subtraction, multiplication and division.

**Punched Board**

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

**Charles Babbage**

In 1822, a mathematician Charles Babbage invented a difference engine for mathematical calculations. In 1842, he developed the Analytical Engine that was automatic. This engine could perform 60 additions per minute.

**Herman Hollerith**

In 1889, Herman applied the idea of punchboards in computers. Ile used punch cards in computers for input and output.

**Atanasoff**

Atanasoff was a professor at Lowa University. He invented an electronic computer. He applied Boolean algebra to computer circuitry.

**George Boole**

George Boole 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 1 Computer (1937-44)**

It is also known as Automatic Sequence Controlled calculator. It was first fully automatic calculating machine. It was designed by Howard A. Aiken of Harvard University. It was very reliable but huge in size.

**The ENIAC (1943-46)**

ENIAC stands for Electronic Numerical Integrator and Calculator. It was invented by J. P. Eckert and John Mauchly in 1946. It was the first electronic computer. It was very heavy and large in size. It consumed 140 Kilo Watts of power. It could perform 5000 additions per second.

**The EDVAC (1946-52)**

EDVAC stands for Electronic Discrete Variable Automatic Calculator. It was developed by Dr. John Von Neumann. It could store instructions and data.

**The UNIVAC (1951)**

UNIVAC stands for Universal Automatic Computer. Eckert and Mauchly formed Eckert-Mauchly Computer Corporation in 1947 to manufacture computers commercially. They manufactured the first successful computer UNIVAC. It was the first computer for commercial use. It was given to the US bureau of census in 1951. It was manufactured both for scientific and commercial applications.

**Commercial Computers**

The first commercial computer was 701. It was introduced by IBM (International Business Machines).