quipu (khipu)

The Inca civilization was characterized by modernities, including more than 30,000km of roads, advanced architecture, distance communication, and a accounting registration system in the so-called quipus.

The quipus were collections of strings with us, in which each collection was like a worksheet, and each string was a cell containing a number (integer or fraction) or operation. About 1500 kilograms survived the European invasion, and are carefully studied.

More: https://rethinkq.adp.com/artifact-khipu-inka-accounting-system/

lifted, with thanks, from:
https://arram.senta-la.cloud/@autobrain/115028263348238652