HISTORY OF COMPUTER SUMMARY.pdf

PRIMITIVE CALCULATORS. ABACUS: Abacus is the first automating counting device for performing arithmetic operations. The abacus is from China and it was invented 2,500 years ago. AL’KHOWARIZMI AND THE ALGORITHM: Tashkent cleric wrote a book on the process of algori...

PRIMITIVE CALCULATORS. ABACUS: Abacus is the first automating counting device for performing arithmetic operations. The abacus is from China and it was invented 2,500 years ago. AL’KHOWARIZMI AND THE ALGORITHM: Tashkent cleric wrote a book on the process of algorithm and basis of software, in the 12th century. EARLY COMPUTATION DEVICE NAPIER'S BONE{1617}: Napier's bone is a multiplication and division tool invented by John Napier. He is the inventor of logarithm, a concept used to change multiplication to addition. Napier's bone was used in Europe until mid 1960s. FOREFATHERS OF MODERN COMPUTER BLAISE PASCAL{1623-62}: Pascal was the son of a tax collector and a mathematical genius. He designed the first mechanical calculator, pascaline, based on gears, at 18 years old. It performs addition and subtraction and works like an odometer. It was built in 1643 and possibly the first mechanical device used for practical purpose. Pascaline was difficult to use because of the French currency system which was not base 10. WILLIAM OUGHTRED: William invented the slide calculator in 1630. It was used for addition and subtraction. However, DELAMAIN also published a similar circular slide rule before oughtred. It may be well that both invented this instrument independently. GOTTFRIED WILHELM VON LEIBNITZ: He was a German mathematician and built the first multiplication and division calculator. It was not reliable due to accuracy of contemporary parts. He also documented the binary system used in all mordern calculators. He called his machine THE STEPPED RECKONER. He sadly died in poverty. GEORGE BOOLE: Invented boolean algebra system of logic using boolean values use to establish inequalities: symbolic use of < or > or used in computer switching and modern use in library searches. CHARLES BABBAGE: He was a British inventor and designed to important machines: Difference engine  Analytical engine Difference Engine: it was designed to compute values of polynomial functions automatically. Analytical Engine: this could be programmed using punch cards. NB: He never built any of these engines due to low funds. LADY ADA BRYON: She was one of the first women mathematicians in England and was the first programmer. She documented Babbage’s work. She wrote an account and a program for the difference Engine for computing Bernoulli numbers. HERMAM HOLLERITH: He developed an electromechanical punched-card tabulator to tabulate the data for 1890 U.S Census. Data was entered on punched cards and was powered by electricity. He formed the Tabulating Machine Company which became International Business Machines (IBM). IBM is currently the largest computer manufacturer. ALAN TURING: He developed a turing matching which is an abstract model and not a physical computer use to capture the notion of what problems can and what problems cannot be computed. Code breaking was turing’s strength and he Colossus a computer to break the German enigma code-100. HOWARD AIKEN: He built the Harvard Mark 1 computer in 1944 based on babages original design. it was based on relays. Grace Hopper worked as a programmer on this computer. It can add or subtract 23 digit number in 3/10 of a second. ELECTRONIC NUMERICAL INTEGRATOR AND COMPUTER (ENIAC): it was the first electronic digital computer operated with vacuum tubes rather electromechanical switches. It has no programs storage-wired into circuitry. It was based on the decimal numbering system. ★Shockley and Bardeen developed the semiconductor which was used instead of vacuum tubes. VON NEUMANN: He was a consultant on the ENIAC project. He formed plants with mauckly and Eckert for a new computer (EDVAC) which was to stop programs as well as data. Almost all modern computers are based on this idea. He also concluded that the binary system was more suitable for computers. It has a random access magnetic storage device.