Peer pressure refers to the influence exerted by a peer group in encouraging a person to change his or her attitudes, values, or behavior in order to conform to group norms. Social groups affected include membership groups, when the individual is "formally" a member (for example, political party, trade union), or a social clique. A person affected by peer pressure may or may not want to belong to these groups. They may also recognize dissociative groups with which they would not wish to associate, and thus they behave adversely concerning that group's behaviors.[citation needed]

In young people, youth peer pressure is considered as one of the most frequently referred to forms of peer pressure. It is particularly common because most youth spend large amounts of time in fixed groups (schools and subgroups within them) regardless of their opinion of those groups. In addition to this, they may lack the maturity to handle pressure from 'friends'. Also, young people are more willing to behave negatively towards those who are not members of their own peer groups. However, youth peer pressure can also have positive effects.

For example, if one is involved with a group of people that are ambitious and working to succeed, one might feel pressured to follow suit to avoid feeling excluded from the group. Sometimes the child is pressuring themselves. They feel like they need the group to be cool. Therefore, the youth would be pressured into improving themselves, bettering them in the long run. This is most commonly seen in youths that are active in sports or other extracurricular activities where conformity with one's peer group is strongest.

PEER PRESSURE ON RISK BEHAVIOUR

While socially accepted kids are the best in high school because of having the most class resources, the most opportunities and the most positive experiences, research shows that being in the popular crowd may also be a risk factor for mild to moderate deviant behavior. Popular adolescents are the most socialized into their peer groups and thus are vulnerable to peer pressures, such as behaviors usually reserved for those of a greater maturity and understanding, such as the use of drugs or sex. Adolescence is a time of experimentation with new identities and experiences. The culture of high school often has its own social norms that are different from the outside culture. Some of these norms may not be especially positive or beneficial. Socially accepted kids are often accepted for the sheer fact that they conform well to the norms of teen culture, good and bad aspects included. Popular adolescents are more strongly associated with their peer groups in which they may together experiment with things like alcohol, cigarettes and drugs. Although there are a few risk factors correlated with popularity, deviant behavior is often only mild to moderate. Regardless, social acceptance provides more overall protective factors than risk factors.