A social group consists of two or more people who interact with one another and who recognize themselves as a distinct social unit. The definition is simple enough, but it has significant implications. Frequent interaction leads people to share values and beliefs. This similarity and the interaction cause them to identify with one another. Identification and attachment, in turn, stimulate more frequent and intense interaction. Each group maintains solidarity with all to other groups and other types of social systems.
Groups are among the most stable and enduring of social units. They are important both to their members and to the society at large. Through encouraging regular and predictable behavior, groups form the foundation upon which society rests. Thus, a family, a village, a political party a trade union is all social groups. These, it should be noted are different from social classes, status groups or crowds, which not only lack structure but whose members are less aware or even unaware of the existence of the group. These have been called quasi-groups or groupings. Nevertheless, the distinction between social groups and quasi-groups is fluid and variable since quasi-groups very often give rise to social groups, as for example, social classes give rise to political parties.