Ships engaged in the tramp trade do not have a fixed schedule, as is the case in liner trade. The route results from specific orders to ship cargo to a particular destination.

Liner ships call at various ports according to a regular timetable, as opposed to tramp ships. More than one ship can operate on a particular line.

Feeder vessels are responsible for the further transport and distribution of containers to smaller ports. Many feeder ships pass through the Kiel Canal from Hamburg to the Baltic Sea area.