Social Groups :-A man is social animal, who can’t live in isolation; most of the routine activity that a man performs is in group. Therefore a social group is collections of human beings. According to Bogardus – A social groups may be thought of a number of persons, two or more, who have some common objects of attentions who are stimulating to each other, who have common loyalties and participate in similar activities.

Primary Group-A Primary group is a small group in which a small number of persons come into direct contact with one another. They meet face to face for mutual help, companionship and discuss on common questions. They live in the presence and thought about one another.

Secondary Group-A secondary group is one which is large in size such as a city, nation or political party. Here, human contacts become superficial and undefined. The relationship of the members are limited in scope and arrived at by much trial and error and in terms of self interest calculations of the members.

Reference groups – Man is an imitative animal. The desire to imitate others individuals is instinctive in him. When one finds another person progressing in life, he also desire to progress like him. He compares himself with other and begins behaving like them in order to reach their status and positions. Such behaviour after comparisons with other is called reference behavior.