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Ayrıntılar The abacus , which emerged about 5,000 y
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İsimThe abacus , which emerged about 5,000 y
AçıklamaThe abacus , which emerged about 5,000 years ago in Asia Minor and is still in use today, may be considered the first computer. This device allows users to make computations using a system of sliding beads arranged on a rack. Early merchants used the abacus to keep trading transactions. But as the use of paper and pencil spread, particularly in Europe, the abacus lost its importance. It took nearly 12 centuries, however, for the next significant advance in computing devices to emerge. In 1642, Blaise Pascal (1623-1662), the 18-year-old son of a French tax collector, invented what he called a numerical wheel calculator to help his father with his duties. This brass rectangular box, also called a Pascaline, used eight movable dials to add sums up to eight figures long. Pascals device used a base of ten to accomplish this. For example, as one dial moved ten notches, or one complete revolution, it moved the next dial - which represented the tens column - one place. When the tens dial moved one revolution, the dial representing the hundreds place moved one notch and so on. The drawback to the Pascaline, of course, was its limitation to addition. In 1694, a German mathematician and philosopher, Gottfried Wilhem von Leibniz (1646-1716), improved the Pascaline by creating a machine that could also multiply. Like its predecessor, Leibnizs mechanical multiplier worked by a system of gears and dials. Partly by studying Pascals original notes and drawings, Leibniz was able to refine his machine. The centerpiece of the machine was its stepped-drum gear design, which offered an elongated version of the simple flat gear. It wasnt until 1820, however, that mechanical calculators gained widespread use. Charles Xavier Thomas de Colmar, a Frenchman, invented a machine that could perform the four basic arithmetic functions. Colmars mechanical calculator, the arithometer, presented a more practical approach to computing because it could add, subtract, multiply and divide...
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Ekleme tarihi: 07.10.2008 16:13
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En son güncelleme 07.10.2008 16:14
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