Tribalism is the state of being organized in, or an advocate for, a tribe or tribes. In terms of conformity, tribalism may also refer in popular cultural terms to a way of thinking or behaving in which people are (excessively) loyal to their own tribe or social group. The social structure of a tribe can vary greatly from case to case, but, due to the relatively small size of customary tribes, social life in those kinds of tribes usually involves a relatively undifferentiated role structure, with few significant political or economic distinctions between individuals.