Part of the flash-mob phenomenon can be attributed to what kids call "party groups," which thousands of city youth join because they want to "be somebody." Membership gives them the status they seek, teens say.

The groups throw parties that draw hundreds of kids, members often sport hoodies bearing the group's name, and they post promotional videos on YouTube. The groups meet at parties, on South Street and on Broad Street and often clash over everything from general dislike and envy to trash-talking that starts on social-networking sites such as Facebook and Tinychat, teens say.

One of the goals is to be voted Party Group of the Year, on a social network page such as Facebook. This distinction was given most recently to Platter boyz, according to Facebook. Some other party groups in the city include:

P.I.F. Divas - Paid in Full Divas

A.B.M. - All About Money

AAS - All Adidas S---

ANS - All Nike S---

Trap Street

H&M Beauties

Bad Boyz

Dream Team

OTS - Official Trap Stars

All Polo S---

A Definite Hit

Here are some phrases kids use today with which adults may not be as familiar:

* They be drawin' - doing something unnecessary

* Did da biz - Depending on how it's used, it can mean that someone was beaten up or that a party was fun.

* Itz gone Do 1 thing - It's going to be crazy, fun.

* The party gone POP - going to be fun.

* The party did the p---- - The party was extremely incredible.

* Buzz - popular.

* CTFU -crackin' the f--- up.

* SMH - shakin' my head.

Examples of messages drawing large crowds:

"South Street gone Do 1 thing 3/15 pass it on"

To notify police about a flash mob, call 215-686-tips.