Slang consists of casual, nonstandard vocabulary and expressions often associated with the way teenagers and young people speak. As I grow older, it becomes more difficult for me to keep up with the slang younger people are using nowadays. So what I do is hang out at the local university and listen to the way students talk. If you want to speak like a teenager, make friends with teenagers. If you want to speak like a manager, make friends with managers. If you want to speak like an American, make friends with Americans. There are books on English slang, but it's best to watch movies and ask your English-speaking friends about the meanings of the expressions you hear. Some slang expressions could already be old ("Everything is groovy") or used only in certain regions of the United States ("Gnarly waves, brah!").

Slang is essentially used all the time. What's up, dawg/dog? = How are you, my friend? Sup = What's up, dawg/dog? Shut up. = Be quiet. Gimme some sugar. = Kiss me. Shoot! = (exclamation of frustration) Those are just some examples.

Wait, now i'm equally confused. I thought slang and street talk were different. example : [slang] a gun is useless without ammo [slang] this town is really an armpit [slang] oh sweetie, did you make another boo-boo ? [street] yo don't be trippin man [street] nice set'o wheels brah [street] dayum that's some bling ya got

yo: hi, what's up aggro: aggressive air-locked: drunk pig: cop

Hi have a look here http://www.italki.com/knowledge/page/ENGLISH%20%20SLANG%20TERMS.htm