An Overhead Bridge Crane (also called an Overhead Traveling Crane) is a crane that is permanently fixed in place for the purpose of maneuvering extremely large and heavy objects that would be unfeasible, if not impossible, to move manually. This type of crane system is constructed by relying on a beam (rail) that is permanently attached to a support structure. Via a cable or wire rope that is fed through the trolley-mounted mechanism, heavy objects can be moved vertically (raised or lowered), while at the same time moved horizontally along the rail, thereby moving the object for new placement. Smaller overhead cranes might be used to move heavy tools, products, or equipment back and forth between workshops or from a workshop to a loading dock.