A term used to describe pretentious indie kids, generally redheads or other incredibly ugly/skinny kids who listen to the whatever the latest shit indie band is and take heaps of fucked up drugs and think they're the shit. These kids are really only in it for the image and wouldn't know good music if it kicked them in the balls.
Quick you gotta listen to this new band dude, it'll up your arty cred points!
Yeah he goes op-shopping for his clothes. He's so Arty Cred.