The worm drive is a gear arrangement in which a worm (which is a gear in the form of a screw) meshes with a
worm gear (which is similar in appearance to a spur gear, and is also called a worm wheel). The terminology is
often confused by imprecise use of the term worm gear to refer to the worm, the worm gear, or the worm drive as a
unit. Like other gear arrangements, a worm drive can reduce rotational speed or allow higher torque to be
transmitted. Figure 5(a) and (b) show the load carrying shaft and worm gear respectively.