[[Image:Caster-wheels-chair.jpg|thumb|left|upright|Two wheeled swivel casters on a [[desk chair]] (no fork)]]
CasterLike wheelsthe aresimpler specialrigid wheelscaster, thata helpswivel objectscaster moveincorporates around.a Thinkwheel ofmounted theto wheelsa onfork, yourbut officean chairadditional or[[swivel ajoint]] shoppingabove cart;the thosefork areallows casterthe wheels.fork Theyto comefreely inrotate differentabout sizes and types360°, but allthus serveenabling the same purpose:wheel to makeroll movingin thingsany easierdirection.<ref>{{citeweb|last1=khanvilkarThis |first1=Rupeshmakes |title=Theit Complete Guidepossible to Heavyeasily Dutymove Casterthe Wheelsvehicle |url=https://swiiftcaster.com/2023/10/12/complete-guide-heavy-duty-caster-wheel/in |website=Swiiftcasterany |access-date=12-10-2023}}</ref>direction without changing its orientation. Swivel casters are sometimes attached to handles so that an operator can manually set their orientation. The improved swivel caster was invented in 1920 by Seibert Chesnutt, US Patent 1341630, which was easily manufactured by stamping, and incorporated ball bearings for longer life. Basic swivel casters were in evidence in Charles Darwin's famous "office chair" as early as the 1840s.
Additionally, a swivel caster typically must include a small amount of offset distance between the center axis of the vertical shaft and the center axis of the caster wheel. When the caster is moved and the wheel is not facing the correct direction, the offset will cause the wheel assembly to rotate around the axis of the vertical shaft to follow behind the direction of movement. If there is no offset, the wheel will not rotate if not facing the correct direction, either preventing motion or dragging across the ground.
