## Pages

### History of Computers

Though the first Electronic general purpose computer (ENIAC) was available in early 1940’s the history of the calculating machine starts as early as 1642 during which the first mechanical calculating machine was developed by basic, Pascal, a brilliant young Frenchman. About 30 years later, Gottfried Von Leibniz, a German mathematician, improved upon Pascal’s invention by producing a calculating machine which could add subtracts, multiply, divide and improvised calculating machine, a major break through was the development of electromechanical punched card equipment invented by Dr. Herman Hollerith, a statistician. In 1887, Hollerith developed his machine, readable card concept and designed a device known as the “CENSUS MACHINE”. In 1896 he founded the tabulating machine company to make add sell his invention. Later this firm merged with others to form what is now known as International Business Machines Corporation (IBM).
Abacus:-

The Stone Age man used pebbles for counting cattle. Latter on when man became more civilized abacus came in use. Abacus seems to be the earliest calculating machine which was developed by Chinese 3000 years ago. Interestingly enough abacuses are still being used in Soviet Union, Japan, Far East and even in India for primary education. It consists of a rectangular wooden frame with horizontal rods. Which carry round beads? Counting is done by shifting the beads on left hand side of cross bar have a value of five and each of the five beads on right hand side of cross bar have a value of one. The topmost line represents the unit digit second line tens digit third line hundreds and so on. Numbers are entered in reverse order starting from top to bottom.

Analog Machines and Napier Bones:-

John nippier the Scottish mathematician devised a set of fords for use in calculations invoicing multiplication. These rods were carved from bones and therefore called as nappies bones.

Odometer (Speedometer) and Logarithm:-

Sometimes later odometer was discovered perhaps before the birth of Christ which led to development of mechanical adders and multipliers. In 1617 john Napier the distinguished Scottish mathematician developed the method of logarithm. Logarithmic tables represent actually analogue computing technique. N this system multiplications and divisions can be done by adding and subtracting not the numbers themselves but with the help of a related numbers known as logarithm. Logarithm is nothing but an application of indices. By use of logarithms arithmetical calculations regarding multiplications division’s square roots and factions can be easily simplified by referring to standard tables. If swore of 3 is nine then 2 is the logarithm of 9 to the base 3. normally base 10 logarithm is used in which case since square of 10 is 100 then 2 is the logarithm of 100 to the base 10. Similarly since cube of 10 is 1000 then 3 is the logarithm of 1000 to the base 10.

Blasé Pascal and his Mechanical Calculator:

The first mechanical calculating machine was made in 1642 by great French mathematician and philosopher Blasé Pascal. His machine was a simple calculator used for addition and subtraction purposes. Pascal invented the calculator at the age of 18 only to assist his father in tax calculations.

Within two years he devised a working modal which was patented in years 1645. The machine consisted of gears, wheels and dials. Each wheel had 0 segments like that of milometer or house energy meters. When one wheel completed a rotation the next wheel moved by one segment. With this calculator addition and subtraction could be performed by dialing these series of wheels bearing and number 0 to 9 around their circumference. The machine was produced in mass scale and became very popular. This machine which was larder on modified by a German Gottfried Leibnitz in 1671 was the first machine to multiply and divide directly.

Charles Babbage:-

Charles Babbage another genius in history of computing made a machine called differential engine which could value accurately algebraic expressions and mathematical table correct up to 20 decimal places. Later on he was able to develop analytical machine which was an automatic computing machine designed to do assertions at the rare of 60 per minute and had memory also. His idea of using cards was derived from the work of Joseph jacquard that in France used punched cards to determine the threads to be selected in weaving partners automatically.