Abacus

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Abacus [abakuhs] A device for performing calculations by sliding bead counters along a set of rods or in grooves, It may have originated in Babylonia, and was used in ancient China, Greece, and Rome. It became widespread in Europe in the Middle Ages, as well as in China and Japan, where it is still in use, though increasingly being replaced by the calculator.

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Communism

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