If you're working with electricity in your home wiring, learning how to identify what wires carry current is a life-saving skill. Household AC (alternating current) circuits have three types of wires: hot, neutral and ground. The hot wire carries a constant flow of electricity from the power source to the load. The neutral wire completes the circuit from the load back to the power source, and the ground wire dissipates excess current into the ground rod.
Remove outlet faceplates.
Look at the wiring connected to the electrical outlet. The wire connected to the smaller side of the socket should always be the hot wire. The wire connecting to the larger rectangular side of the socket should correspond to neutral.
Look at the colors of the wires. Generally, black should correspond to the hot wire and white to neutral.