Well, guys as a general rule fart far more freely then girls do. So whenever I'm hanging around with guys they fart all the time and think nothing of it, but if I'm with my girlfriends, unless its a really close girlfriend, then we kind of dont...or if we do we act like we havn't.

It was all different when I was younger however, we used to fart all the time, the louder the funnier. I never did loud ones though