When your fart opens your anus releasing a wad of air while producing no noise.This fart can either be stinky or have no smell at all. If your stomach hurts than your fart will be hot and smelly.

While at the office, casually walk over to a co-worker as if you have important news. When their guard is down, drop trousers, and in one motion, spread your ass-cheeks as far as possible with your hands and bend over releasing pure gasseous matter directly into the unsuspecting victims face. AKA: OBH (open butthole fart)