The oldest use of family or surnames is unclear. Surnames have arisen in cultures with large, concentrated populations where single names for individuals became insufficient to identify them clearly. In many cultures, the practice of using additional descriptive terms in identifying individuals has arisen. These identifying terms or descriptors may indicate personal attributes, location of origin, occupation, parentage, patronage, adoption, or clan affiliation. Often these descriptors developed into fixed clan identifications which became family names in the sense that we know them today.