Quipu (khipu) with top and subsidiary cords

Andean cultures did not have a recognizable writing system prior to the Spanish conquest in the early 1530s; however, they did utilize a system of recording through knotted cords, known as quipu (khipu; “knot” in Quechua). Quipu that date to the Late Horizon and early Spanish colonial period (1400–1570 C.E. ) vary in structure, from numeric records to “anomalous” types that possibly record more abstract concepts. Spanish chroniclers cite their use by specialists, known as quipucamayoc (khipucamayuq), for recording census, taxes, and stored goods such as dried maize and potatoes. Early forms of quipu were used during the Middle Horizon (600–1000 C.E.), under Huari (Wari) cultural influence.

This Inca-style quipu exhibits a numerical structure based on the Andean decimal system. The number of loops in a knot indicates the numerical value, while the placement of the knot along the vertical subsidiary cord references its place value (1s, 10s, 100s, 1000s, 10000s). Different fibers and knot directions were employed, perhaps as markers of particular information.