A switcher, shunter, yard pilot, switch engine, yard goat, or shifter is a small railroad locomotive used for manoeuvring railroad cars inside a rail yard in a process known as switching (US) or shunting (UK). Switchers are not intended for moving trains over long distances but rather for assembling trains in order for another locomotive to take over. They do this in classification yards (Great Britain: marshalling yards). Switchers may also make short transfer runs and even be the only motive power on branch lines and switching and terminal railroads. The term can also be used to describe the workers operating these engines or engaged in directing shunting operations. Switching locomotives may be purpose-built engines, but may also be downgraded main-line engines, or simply main-line engi