Step Reckoner

• It was invented in 1673
• The Step Reckoner was the first true four-function calculator. It was invented by Gottfried Wilhelm Von Leibriz.
• The step reckoner's rotating drum and a counter mechanism approach inspired calculator design for centuries. It was also used to make computing with binary easier.
• A cool fact about the Step Reckoner is that Leibniz worked on perfecting the step reckoner for over 45 years.