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Multiplying Bones
"Napier's bones" invented by John Napier for multiplication, based on the ancient numerical scheme known as the Arabian lattice. -
Period: to
Calculator Timespan
The History of Calculators -
Calculating Clock
Willhelm Schickard invented the "Calculating Clock", the first mechanical calculator. It used a version of Napier's bones for multiplication with a mechanical adding/subtracting calculator based on gears, with mutilated gears for carry. -
Pascaline
Blaise Pascal started to develop a mechanical calculator - the Pascaline. Capable of addition, subtraction was performed by nines-complement addition, and multiplication was performed by repeated additions and subtractions. It had shortcomings and failed to sell. -
Stepped Reckoner
Gottfried Leibniz developed the Stepped Reckoner using stepped gear wheels. Performed the 4 functions, but worked off and on due to an error in the carry mechanism, none sold. -
Arithmometer
Charles Xavier Thomas's Arithmometer. -
Scheutz Difference Engine
The Scheutz Difference Engine completed: the world's first printing calculator. -
Pinwheel Calculator
W.T. Odhner in Sweden independently develops the pin-wheel calculator. Since then, many calculating machines have used the same principle. -
Madas 20BZS
Madas 20BZS , a typical electrically driven, stepped-gear calculator with automatic multiplication and division. -
Anita Mk 8
the Anita Mk 8 for all markets but the continental European market. These models used cold-cathode vacuum tubes and numerical display ("Nixie" type) tubes. -
Hewlet-Packard HP35
First scientific pocket calculator introduced was the Hewlet-Packard HP35 . -
Sharp PC1211 / Tandy TRS80 PC-1
The Sharp PC1211 / Tandy TRS80 PC-1 is the first hand-held computer; it has a QWERTY keypad and runs the BASIC language.
