A volt is a measure of electrical pressure, as it runs along a conductor. The average home is supplied with 240 volts, which is divided into three wires: two 'hot' wires of 120 volts each, and one neutral ground wire. Because power naturally fluctuates throughout the day, the actual voltage on a circuit designated as '120' may vary between 110 and 120 volts. From the service panel, wiring is run throughout your home in various configurations, depending on what device it feeds. Typically, 120-volt wiring is used to connect electrical outlets and small appliances like the refrigerator. High-powered items like your air conditioner, dryer, and kitchen stove require 240-volt wiring; this is created by combining both of 120-volt wires. For those with unusual power demands, such as operating a machine shop, 480-volt wiring may be necessary. This power would come directly from the pole; however, it requires special wiring, and is usually done by the electric company. To find out more about 120, 240 and 480 volt-wiring, consult an experienced electrician, or your local power company.