Troops move and fight in a tight formation of one or more ranks. While they move they must maintain their formation, which means that individual models are not free to wander off on their own. The formation can move straight forward as a body perfectly easily, but if it wishes to change direction then it must make a manoeuvre.

There are three specific manoeuvres which enable a unit to turn about or rearrange its ranks, these are wheel, turn or change formation.