A quipu usually consisted of colored, spun, and plied or waxed thread or strings made from cotton or camelidfiber. The Inca people used them for collecting data and keeping records, monitoring tax obligations, properly collecting census records, calendrical information, and for military organization. The cords stored numeric and other values encoded as knots, often in a base tenpositional system. A quipu could have only a few or up to 2,000 cords. The configuration of the quipus has been "compared to string mops." Archaeological evidence has also shown the use of finely carved wood as a supplemental, and perhaps more sturdy, base to which the color-coded cords would be attached. A relatively small number have survived.
Objects that can be identified unambiguously as quipus first appear in the archaeological record in the first millennium AD. They subsequently played a key part in the administration of the Kingdom of Cusco and later Tawantinsuyu, the empire controlled by the Inca ethnic group, flourishing across the Andes from c. 1100 to 1532 AD. As the region was subsumed under the invading Spanish Empire, the use of the quipu faded from use, to be replaced by European writing and numeral systems. However, in several villages, quipu continued to be important items for the local community, albeit for ritual rather than practical use. It is unclear as to where and how many intact quipus still exist, as many have been stored away in mausoleums
The word "khipu", meaning "knot" or "to knot", comes from the Quechua language word: quipu, 1704, the "lingua franca and language of administration" of Tawantin Suyu.
"The khipu were knotted-string devices that were used for recording both statistical and narrative information, most notably by the Inka but also by other peoples of the central Andes from pre-Inkaic times, through the colonial and republican eras, and even – in a considerably transformed and attenuated form – down to the present day."