Chassis system: Containers are placed on or picked up from semitrailers by
shipside cranes, The trailers are pulled to and from the yard by tractors. While in the
yard, containers are stored on the trailers.
Straddle carriers: They pick up and deliver containers at the apron and in the
yard, stack containers two or three high and remove them from the stacks.
Gantry cranes: They can be either on rubber wheels or on rails and containers
can be stacked 3-5 high. They can be combined with chassis system.