Usually unplanned and a spur of the moment occasion. it is usually asked by one person to another after one has pissed off another.
other guy: oh yeah well you're a faggot!
guy: i know u weren't talkin to me!
other guy: yeah i was!
guy: alright lets throw ones off the bus.
other guy: alright lets go
bystander: shit they bouta be throwin ones!