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High Quality Content by WIKIPEDIA articles! The Step Reckoner (or Stepped Reckoner) was a digital mechanical calculator invented by German mathematician Gottfried Wilhelm Leibniz around 1672 and completed in 1694. The name comes from the translation of the German term for its operating mechanism; staffelwalze meaning ’stepped drum’. It was the first calculator that could perform all four arithmetic operations: addition, subtraction, multiplication and division. 3
