Humans are social beings who have organized into groups and societies throughout history in order to bond, survive, and fulfill various needs. Groups provide a sense of belonging, socialization, and transmission of culture. While not all collections of individuals form true social groups, authentic groups are characterized by regular interaction and communication among members who share common experiences, identities, and interests. Societies contain various types of groups that serve different purposes, from intimate primary groups to large, impersonal organizations. Group membership and reference groups help shape individuals' identities and behaviors.