The Incas had a system of accounting that relied on the quipu. Cords of various colours were attached to a main cord with knots. The number and position of knots as well as the colour of each cord ...

The structure was dubbed Quipu (pronounced KEE-poo) after an Incan system of recording information using knotted cords, by the team at the Max Planck Institute for Physics in Munich, Germany ...

A preprint is available on the arXiv server. Quipu was named after the knotted cords used as recording devices by the Inca Empire and other South American cultures. It resembles those cords ...

While much of the world used stone tablets or other media that didn’t survive the centuries, the Incas used something called quipu which encoded numeric data in strings using knots. Now the ...