In-group: An in-group is a social group to which an individual psychologically identifies with and feels a sense of belonging, often in contrast to an out-group.
Social Identity:Social identity refers to an individual's sense of self-concept derived from their membership in a social group, and the emotional and evaluative significance they attach to that membership.
Prejudice:Prejudice is a preconceived, often negative, attitude or opinion about a person or group based on limited information or experience, rather than on reason or actual knowledge.