Why do people stereotype teenagers?

I don't think that it's just teenagers who have stereotypes thought about them. Everybody is subject to at least one stereotype whether that's because of their hair, height, gender, sexuality, taste in music; or many more things. There's just something about the human race which makes us want to put people into groups, and therefore we think that all people who are members of that group are likely to behave in the same way whether they would do in reality or not. I am not sure why we think like this, but it is something that has been going on for many years now so I think that it is very unlikely to stop now.

I don't know but it annoys me to the point of crying.I am a teenager and I act nothing like those stereotypical teenager on TV shows,books,jokes,etc. It just makes me so mad that they don't give me any right of decisions,because I'm a 'kid' but they still expect me to take on many responsibilities because I am an 'adult'. As a teenager I can say that 80% of the stereotypes are ridiculous,simply untrue or downright offensive.I feel more like an adult then a kid and I expect some more respect but still,there is nothing a person can do except subvert the stereotypes and hope for the best...