When your confused and dont no whats going on you say this.Tommo usally uses this cause he is always confusede and doesnt no whats going on.
Ben:Fuhkn oi bra cumom what the fuck you doing.
Tommo:I just stacked and the pain wont go away its hurting bad shit.
Ben:hahahahah
Tommo:arhhhhh whats happening.
1) a question when one is curious about what is going on around him.
2)A popular greeting greating used instead of "hello".
3) A state of confusion when used in a situation where both definitions intertwine.
eg. when you have just met someone whom you know and who may be curious about a situation or the goings on around you.