Amazing Old Calculator (Curta)

Alex Bellos discusses how the Incans used knots in string (Quipu) to record numbers.Check out Brilliant (get 20% off their premium service): https://brillian...

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The Curta is a pocket-sized, mechanical, digital calculator!!! It was invented by Curt Herzstark.

Shown here by Alex Bellos, author of Alex's Adventures in Numberland.

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