I watched the OC, and listened a queation in it! What the help is going on? (am I spell right?) I want to ask is it same meaning of What happened? What's up?

I'm waiting for your reply! thanks a lot!
I have no idea what OC is, but I presume you mean What the h e l l is going on, which has the same meaning as What is happening; however, h e l l is an intensifier of questionable propriety, and should not be used by non-native speakers unless they are adept in the language.

No, "what's up" is not impolite, but it's something you'll say to your friends. That's what Bugs Bunny always says to the little pig(I don't remember his name) "Hey, what's up, doc?"!
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The OC is the tv programme ! I practice the listening through this tv programme! so, this sentence is learn from that!

Is native speaker will always say that?

And "What's up?" is it impolite ? Is just can say with our friends will be better?
 pieanne's reply was promoted to an answer.
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Dear friends,

«What's up?» is «what is the matter?»

«What's up!» is a greeting between friends.

I do not know if Bugs Bunny means the first or the second. Emotion: smile

With best wishes, Emotion: smile