sually, the storage space of container ships is measured in terms of Twenty-foot (6 meters) Equivalent Units (TEUs). Most shipping containers come in lengths of either 20 or 40 feet, meaning that the ship can be efficiently packed to capacity with a collection of shipping containers. On small container ships, rigging equipment is attached to the ship so that it can be loaded or unloaded anywhere. On larger container ships, the ship has no rigging equipment, and must be docked in specific ports with cranes that are capable of working with the very large ship.