Rate of Fire

Rate of Fire is the frequency at which a specific weapon can fire its projectiles, or magic attack for wands. This correlates to ranged attack speed.

Rate of fire directly affects the speed of attack for weapons for which the character has the autoshot ability (mages, priests, and warlocks with wands, and hunters with bows, crossbows, or guns). For shots or throws which must be manually initiated, the manual triggering process tends to overshadow the rate of fire; still the manual shot is available sooner.

Hunters' Auto Shot grants a 15% ranged haste bonus.

On Wikipedia