An engine primarily used to move and position cars on different tracks, such as in a yard.

A switching locomotive, used for shifting or switching cars in yards and terminals.

A locomotive designed typically for yard service, which calls for good visibility from the cab and pulling power rather than speed.

A road assignment that spots, pulls, and classifies cars within a terminal or industrial area.

A switcher or shunter (Great Britain: shunter; USA: switcher, except Pennsylvania Railroad: shifter) is a small railroad locomotive intended not for moving trains over long distances but rather for assembling trains ready for a road locomotive to take over, disassembling a train that has been brought in, and generally moving railroad cars around - a process usually known as switching (UK: shunting). They do this in classification yards. Switchers may also make short transfer runs and even be the only motive power on branch lines.