History Of Computer And Generations.pdf

BY ZOHAIB HASSAN 1 History of Computer and Generations History: THE ABACUS Abacus is known to be the first mechanical calculating device. Abacus is made up of wooden frame in which rod where fitted across with rounds beads sliding on the rod. It is dividing into two parts called Heaven and Earth. Heaven was the upper part and Earth was the lower one. Thus any no. can be represented by placing the beads at proper place. NAPIERS BONES As the necessity demanded, scientist started inventing better calculating device. In thus process John Napiers of Scotland invented a calculating device, in the year 1617 called the Napier Bones. In the device, Napiers used the bone rods of the counting purpose where some no. is printed on these rods. These rods that one can do addition, subtraction, multiplication and division easily.BY ZOHAIB HASSAN 2 PASCALS CALCULATOR In the year 1642, Blaise Pascal a French scientist invented an adding machine called Pascals calculator, which represents the position of digit with the help of gears in it. LEIBNIZ CALCULATOR In the year 1671, a German mathematics, Gottfried Leibniz modified the Pascal calculator and he developed a machine which could perform various calculation based on