He is a well known-ish actor who starred in the disney film high school musical, which kicked of his career. He has done films before this also. His most reccent film is called 17 again.
Basically zac Efron=HOTNESS ;)
"He belongs in a museum for hotties!"
"You wish.Twitty little fangirls."
you: yeah he never looks bad, he is just naturally hot
girl: what do you get, if a shark and an iguana had a human baby, and it had downsymndrome?
boy: O_o what?
girl: zac efron! DUH!
I know he is amazing!