Overhead cranes consist of several interconnected parts that work together to lift, move, and lower heavy loads safely and efficiently.    An overhead crane is a complex system, and its parts can be categorized into three major groups: the bridge, the hoist/trolley, and the end trucks..    This is based on standard designs for bridge-style overhead cranes (the most common type), though variations exist depending on whether it's a single-girder or double-girder model.