The quipu is a traditional Andean counting device that uses colored strings and knots in lieu of paper and numbers.

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 ...

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 ...

The quipu, an ancient Peruvian form of a spreadsheet ... years’ tuition in making and using quipus. Quipus were knotted-string devices used for recording statistics on production, storage ...