One of the most practical uses of circuits and the many concepts of circuit use is in the household. Household circuits are a very practical application of all the concepts that we have learned using circuits. In a typical neighborhood, the Power Company distributes electric power to individual houses with a pair of wires, or power lines. A circuit in a house is then connected in parallel to these lines. The potential difference between the two wires is about 120V in the United States. One of the wires is connected to the ground, and the other wire, sometimes called the "hot" wire, has an average potential of 120V. A meter and circuit breaker, or in other cases a fuse, are connected in series with the wire entering the house.