When was the First Calculator Made?

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Abacus was the first instrument to help people make calculations. Developed in Babylonia in about 3000 B.C., it had beads that moved along wires in frame to represent numbers. The first calculating machine was built by a French scientist, Blaise Pascal in 1642, when he was just 19 years old. This calculator could only add and subtract numbers. Numbers were fed into the calculator by operating wheels, which turned the gears inside. The gears then moved dials with numbers so that the result showed in a set of windows. The first calculating machine that could multiply and divide was invented by a German scientist, Gottfried Leibnitz in 1694. In the 1970s electronic calculators were used widely.

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