 The "track" determines what areas of terrain the tank can cross.These included "wheels", tracks which can only cross basic terrain, such as stone, "half-tracks", tracks which can cross desert, "snow-mobiles", tracks which can cross over snow, "boats", which can cross over water, and "hover-crafts", tracks which can cross over anything without suffering the effects of the ground.Making tanks without tracks renders them immobile, similar to turrets.