What is the difference between a clique and a crowd?

A clique is a group of usually about five or six (could be as small as two or as large as 12) who are the same gender and age.These groups are defined by common activities or just because they are friends. These people are your closest friends, the ones you feel the most comfortable around and interact with the most.
Crowds are based on stereotypes. A stereotype is an oversimplified conception. When a teen enters high school, they are generally labeled and associated with a crowd that shares some common feature. For example, crowds can be based on ethnicity or neighborhood, a way of dress or behavior, or a common interest. Typical crowds in many high schools include: “jocks,” “populars,” “nerds,” “brains,” “Goths,” and “druggies.

So, crowds are not based on who your friends actually are; they are simply the category you are stereotyped into. Crowds don’t influence a teen’s social choices as much as cliques (since cliques are a teens’ real friends), but crowds do have a huge influence on a teen’s identity. This is because teens often see themselves the way they think others see them. That is, when someone else thinks you act a certain way, you may end up changing the way you act so you fit the stereotype.