DeFRaG (also capitalised as defrag, abbreviated as df) is a free software modification for id Software's first-person shooter computer game Quake III Arena (Q3A). The mod is dedicated to player movements and trickjumping. It aims at providing a platform for self-training, competition, online tricking, machinima making, and trickjumping. Hence it constitutes an exception among other Q3A mods. The modification was released to the public in ca. September–October 2000. In 2002 DeFRaG was selected as "Mod of the Week" at Planet Quake.