Family is also called clan, household and house. In ancient books, it is often called clan and clan directly, and family members are called clansmen and clansmen. The scope of these nouns at that time was inconsistent and uncertain. Some scholars try to distinguish the two nouns, family and clan, and put forward that five clothes are clan and five clothes are family, which is really unnecessary and impossible to distinguish.

There were so-called "three clans" and "nine clans" in ancient times. According to the explanation of the Han people, there are three parents and wives, or two parents and wives, or nine from grandfather's uncle to the Great-Grandson Nine Dynasties. In ancient times, the so-called "clan rule" and "unification of nine clans" actually implicated all clans in the same high-ancestor, and both the mother clan and the wife clan, which was extrajudicial punishment. The family is centered on the nine most closely related families. As for matriarchal line and wife line, they are used for different surnames.

Clans in primitive society, including lineage clans and paternal clans, are also families formed by blood ties in a sense. However, the clan system and the family system we are talking about are different in principle. Clans are not United on the basis of a single family. They are not all descendants of male ancestors. They do not have the basic characteristics of the family system that has existed and developed for thousands of years, nor are they strictly family.