氏族一般是这样一种组织，其成员有一共同祖先或有一想象的共同祖先，其成员一般不可能是另一个氏族的成员，成员之间有特别密切的关系、权利和义务，氏族有自己独特的称号，一般来说氏族内部成员之间不通婚。氏族一般作为部落的成员而存在！

氏族产生于旧石器时代晚期。依照计算其世系划分氏族的方式可分为母系氏族和父系氏族；子女成为母亲所在氏族成员的是母系氏族，子女成为父亲所在氏族成员的是父系氏族；氏族为母系氏族的社会状态为母系社会，氏族为父系氏族的社会状态为父系社会；一般认为母系社会早于父系社会，父系氏族是由母系氏族演化产生的。

A clan is a group of people united by actual or perceived kinship and descent. Even if lineage details are unknown, clan members may be organized around a founding member or apical ancestor. The kinship-based bonds may be symbolical, whereby the clan shares a "stipulated" common ancestor that is a symbol of the clan's unity. When this "ancestor" is non-human, it is referred to as a totem, which is frequently an animal. The word clan is derived from clann meaning children or progeny but not family in the Irish language and Scottish Gaelic languages. According to the Oxford English Dictionary, the word was introduced into English around the year 1425 as a label for the nature of the Scottish Highlands society. Clans in indigenous societies are likely to be exogamous, meaning that their members cannot marry one another. Clans preceded more centralized forms of community organization and government; they are located in every country. Members may identify with a coat of arms or other symbol to show they are an independent clan.