In sociology, a peer group is both a social group and a primary group of people who have similar interests (homophily), age, background, or social status. The members of this group are likely to influence the person's beliefs and behaviour.
Peer groups contains hierarchies and district patterns of behaviour. In a high school setting for example, 18 year olds are a peer group with 14 year olds because they share similar and parallel life experiences in school together. In contrast, teachers do not share students as a peer group because teachers and students fall into two different roles and experiences.
During adolescence, peer groups tend to face dramatic changes. Adolescents tend to spend more time with their peers and have less adult supervision. Adolescents communication shifts during this time as well. They prefer to talk about school and their careers with their parents, and they enjoy talking about s*x and other interpersonal relationships with their peers.

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