Answer by
dfgospgfj (164)
In 2-wire Romex, black is the hot wire, white is the neutral, and the uninsulated wire is the ground. In 3-wire Romex, everything in the previous sentence remains true, but there is an additional red wire. The red wire is most often used in wiring 3-way and 4-way switch. In these cases, it is referred to as the "traveler. "