Quipu

Quipu ( KEE-poo), also spelled khipu (Ayacucho Quechua: kipu, [ˈkipu]; Cusco Quechua: khipu, [kʰipu]), are record-keeping devices fashioned from knotted cords. They were historically used by various cultures in the central Andes of South America, most prominently by the Inca Empire.

A quipu usually consists of cotton or camelid fiber cords, and contains categorized information based on dimensions like color, order, and number. The Inca, in particular, used knots tied in a decimal positional system to store numbers and other values in quipu cords. Depending on use and the amount of information stored, quipus can have anywhere from a few to several thousand cords.

Objects which can unambiguously be identified as quipus first appear in the archaeological record during the 1st millennium CE, likely attributable to the Wari Empire. Quipus subsequently played a key part in the administration of the Kingdom of Cusco of the 13th to 15th centuries, and later of the Inca Empire (1438–1533), flourishing across the Andes from c. 1100 to 1532. Inca administration used quipus extensively for a variety of uses: monitoring tax obligations, collecting census records, keeping calendrical information, military organization, and potentially for recording simple and stereotyped historical "annales".

It is not known exactly how many intact quipus still remain, as many were deposited in ancient mausoleums or later destroyed by the Spanish. However, a recent survey of both museum and private collection inventories places the total number of known extant pre-Columbian quipus at just under 1,400.