Tractor Beam
any device which is used to immobilize and move an object. They are modified force fields which employ a graviton-flux beam to alter the shape of the surrounding space-time fabric. The shape is altered so that the target is caught on a ripple of fabric and then "rolled" back toward the generator. Thus, tractor beams can be used to maneuver ships in docking bays, as well as to contain a fleeing ship. In some instances, large tractor beams can also be used to destroy smaller ships by creating a large enough ripple to crash into the target.