Modern HOm trains run on realistic-looking two-rail track, which is powered by direct current (varying the voltage applied to the rails to change the speed, and polarity to change direction), or by Digital Command Control (sending commands to a decoder in each locomotive).
gauge | American wire gauge | Indian gauge | Nuclear density gauge | Durango and Silverton Narrow Gauge Railroad | Apsheronsk narrow-gauge railway | Alexander Gauge | UK National Tide Gauge Network | OO gauge | Nevada County Narrow Gauge Railroad | Narrow gauge railway of Decor-1 factory | Narrow gauge lines of the Victorian Railways | Iberian gauge | Gauge (instrument) | Gauge Change Train | Gauge (bore diameter) | Fluid dynamic gauge |