Sorry if this is not the "right place" for my question. Anyway I'll try.
I'm doing my final dissertation at Uni about slang and I would like to ask to english speaking people which are according to them the 5 most used slang words on tv series or films. Not only those that are becoming standard english such as "cool" or "nerd" but also the ones that you can't fint on a dictionary.
Thank you very very much to anyone will be able to help me!
the problem is that... What is "slang" and what is "informal standard English"? My dictionaries say "cool" is not slang. Not even "sweet". They say "informal", period. As for "dude", one says it's informal, the other says it's actually slang.

So, in my opinion, what you often hear on TV is already standard English, and everybody knows what those terms mean. But if you still want to say it's slang, then what is slang and what is informal English?
Difficult to say as different agegroups/geographic areas/types of people use different slang, and the programmes and films aimed at them will use their slang rather than others. I don't know that you could pin it down just from individual's perceptions, you'd need to do a full survey. Someone who watches Eastenders (a London-based soap opera) would tell you completely different words to someone to watches Coronation Street (a Manchester-based soap opera), to someone who watches Hollyoaks (a soap opera for teenagers).