In human context, a family (from Latin: familia) is a group of people affiliated by consanguinity, affinity, or co-residence. In most societies it is the principal institution for the socialization of children. Anthropologists most generally classify family organization as matrilocal (a mother and her children); conjugal (a husband, his wife, and children; also called nuclear family); and consanguineal (also called an extended family) in which parents and children co-reside with other members of one parent's family.
There are also concepts of family that break with tradition within particular societies, or those that are transplanted via migration to flourish or else cease within their new societies. As a unit of socialization the family is the object of analysis for sociologists of the family. Genealogy is a field which aims to trace family lineages through history. In science, the term "family" has come to be used as a means to classify groups of objects as being closely and exclusively related. In the study of animals it has been found that many species form groups that have similarities to human "family"—often called "packs." Sexual relations among family members are regulated by rules concerning incest such as the incest taboo.