ABSTRACT
Human beings cannot survive living in total isolation from other people. During our lives, we join various groups, voluntarily or forcibly, deliberately or by chance. People tend to form groups in all known human societies (Coon, 1946). A group consists of two or more figures forming a complete unit in a composition. Groups to which we belong are called in-groups, and groups to which we do not belong are called out-groups. Geographic proximity is not a necessary or sufficient condition for belonging to the same in-group. For instance, a Catholic and a Protestant may live side by side in a town in Northern Ireland, but they will probably not belong to similar in-groups. Almost every group to which one of them belongs-a school, a church, or a circle of close friends-will be an out-group for the other. Alternatively, a Hindu boy from New York and a Muslim child from California may never see each other in person, but they can belong to the same fantasy baseball league on the Internet.
