Students at Stanford University mooning at a well-attended protest (and world record attempt) in May 1995
Mooning is the act of displaying one's bare buttocks by lowering the backside of one's trousers and underpants without exposing the front side, bending forward. It is generally considered a rude and disrespectful or insulting act, but is much less offensive than flashing. It is often performed as a form of protest or simply for fun. Mooning is sometimes performed from a moving vehicle. The act of placing one's buttocks against glass while mooning (for example, a car window) is known as a pressed ham.
See also Indecent exposure.