The presence of all three colors—red, black, and white—in a junction box often indicates a switch loop or a multi-way switch configuration. In a switch loop, power might be delivered to the light fixture first, and then a cable runs down to the wall switch. Understanding this color code is necessary for performing residential electrical work safely and correctly. Before touching any wires, locate the circuit breaker. The various colored wires that you can see when you look behind a switch or an outlet are not an accident, but rather a safety feature that is built in. Wires inside an NM (Non-Metallic) sheathed cable are color-coded. The chart is used to identify the different colours of wire used to connect different devices and determine the live, neutral, and ground wires.