what are "chavs" like and why do people not like them on street corners?

[Lozza]

Stereotype is:
Teenagers, although the age range can vary dramatically.
Young people, as opposed to older people though.
Wearing things like designer trainers/tracksuits/hats, along with anything else that looks vaguely flashy (although in an attempt to look flashy it ends up looking ridiculous most if not all of the time).
Working-class or unemployed etc. and so tend to hang around places in groups more, although you could say that of any class really.
Difference is chavs are any of the ones who are particularly loud, confrontational and in-the-way.
They probably just shout things at people out of a combination of boredom and dislike for people who look different to them. But there are a hell of a lot of reasons for antisocial behaviour so who knows.