Why do people form a group? Answer: People form groups for a variety of reasons, from feeling that they belong, to fighting a war. Simply creating the groups creates prejudice and conflict between them. People are usually careful who they pick as teammates. However, there is never enough time nor enough opportunity to know every member well and realize which group is really the best choice. Thus, people form groups based on a few positive criteria, and then develop biases in favor of their group and against the others. Consequently, each person thinks their group is the best, according to their biases and prejudices. People form groups to use its numerous benefits. Members of a group help each other in need, cooperate to reach goals, share resources, and, last but not least, provide opportunities for social interaction, companionship, and support. However, the members only receive the benefits that reflect their behavior.