Crowd psychology, also known as mob psychology, is a branch of social psychology. Social psychologists have developed several theories for explaining the ways in which the psychology of a crowd differs from and interacts with that of the individuals within it. Major theorists in crowd psychology include Gustave Le Bon, Gabriel Tarde and Sigmund Freud. This field relates to the behaviors and thought processes of both the individual crowd members and the crowd as an entity. Crowd behavior is heavily influenced by the loss of responsibility of the individual and the impression of universality of behavior, both of which increase with crowd size.