What was an Inca ayllu?

There were ayllus in Hanan Cusco (upper) and Hurnin Cusco (lower). Each Sapa had his own Allyu. For example, Pachacuti's descendants formed the Hatun ayllu and Topa Inca Yupanqui's desendants formed the Qhapaq ayllu. Members of an ayllu were responsible for maintaining the lands, crops, and animals on the land in which their Sapa had found.