Here are descriptions of common labels given to people in society (note that not all of them are 100% correct):
Goth/Emo: Wears lots of black (such as clothes from Hot Topic), has pale skin, wears lots of makeup (even if it's a guy), dyes their hair dark colors, listens to rock and metal music which talk about sad stuff, cut themselves, and cry alot.
Thug/Gangsta: Wears clothes twice their size, pulls down their pants to show their boxers, wear lots of chains around their neck, talk in ebonics, listen to rap and hip-hop, loves smoking and doing other drugs, constantly engages in criminal behavior such as vandalism or robbery, and (usually) are black, or PRETEND to be black.
Prep: Loves shopping at stores such as Abercrombie and Fitch, wears lots of pink, frequently wears short revealing clothes such as miniskirts or mini tanktops, listens to pop music, speaks with exaggerations on many words such as "like, oh my GOD, that is SOOOOO kewl!", is self-centered and conceited, and usually have blonde hair (which might be dyed as well).
Punk/Skater: Wears clothing such as ripped faded jeans, plaid shorts, studded belts, band shirts, etc., has a mohawk (in which the spikes may have dyed colors), doesn't give a shit about what everyone thinks of them, wants to rebel against society, loves to skate, smokes or does other drugs, and of course, listens to punk rock.
Jock: Wears lots of sports-related clothes such as basketball jerseys, has sneakers such as Nike's or Adidas, works out a lot, like the prep is self-centered and conceited, puts on lots of deodorant, (obviously) loves to play sports, and when not playing, watches them on TV (ESPN, for example), and lastly, can't pass an academic grade at school if his life (or rather, his professional career) depended on it.
Labels are not 100% accurate - they're more of a stereotypical view of today's people, and many find this disrespectful. However, it is also true that labels can help classify a certain type of person that another might be looking for. Just don't expect for the person to be exactly like the label is described.
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