A khipu consists, minimally, of a main cord from which pendant cords hang. Knots tied in the pendant cords and other modifications of the pendant are the commonest data-bearing or significant features. The majority of known specimens utilize an Inka system for numerical recording, deciphered by Leland Locke in the 1920's. Knots upon the lowest part of the pendant represent units, and successive knot clusters ascending toward the main cord register tens, hundreds, and thousands. The principle is a true decimal system, although it has no explicit symbol matching the zero of Arabic numbers.
Some cords contain totals or other arithmetical derivatives of pendant cord numbers.
However, well-informed early colonial writers insisted that not all khipus were of this statistical kind. Some reportedly encoded histories or poems. The warehousekeeper is extending a cord record or khipu , which contains records of goods in the storage chambers. On each cord there are clusters of knots. The collection of clusters on each cord form a symbolic representation of a number.