Range of motion (or ROM), is the linear or angular distance that a moving object may normally travel while properly attached to another. It is also called range of travel (or ROT), particularly when talking about mechanical devices and in mechanical engineering fields. For example, a volume knob (a rotary fader) may have a 300° range of travel from the "off" or muted (fully attenuated) position at lower left, going clockwise to its maximum-loudness position at lower right.