Social Interaction: The process by which people act and react in relation to others, including verbal and nonverbal communication, as well as the exchange of thoughts, feelings, and behaviors.
Social Cognition:The study of how people perceive, remember, and think about social information, including how we make judgments and decisions about ourselves and others.
Social Identity: The part of an individual's self-concept that derives from their knowledge of their membership in a social group, along with the emotional and value significance attached to that membership.