Within a culture, some descent groups may be considered to lead back to gods or animal ancestors (totems).This may be conceived of on a more or less literal basis.There are four main headings that anthropologists use to categorize rules of descent.
Human kinship relations through marriage are commonly called "affinity" in contrast to the relationships that arise in one's group of origin, which may be called one's descent group.
In some cultures, kinship relationships may be considered to extend out to people an individual has economic or political relationships with, or other forms of social connections.
the difference between a mother and a childless woman).
Degrees of relationship are not identical to heirship or legal succession.
Family is a group of people affiliated by consanguinity (by recognized birth), affinity (by marriage), or co-residence/shared consumption (see Nurture kinship).
In most societies it is the principal institution for the socialization of children.
As the basic unit for raising children, Anthropologists most generally classify family organization as matrifocal (a mother and her children); conjugal (a husband, his wife, and children; also called nuclear family); avuncular (a brother, his sister, and her children); or extended family in which parents and children co-reside with other members of one parent's family.
However, producing children is not the only function of the family; in societies with a sexual division of labor, marriage, and the resulting relationship between two people, it is necessary for the formation of an economically productive household.
Kinship can also refer to a principle by which individuals or groups of individuals are organized into social groups, roles, categories and genealogy by means of kinship terminologies.