Current is the flow rate of electrons. Current is measured in amperes (amps or A). Voltage is the pressure behind the electrons. Voltage is measured in volts (V). Electric power is measured in watts (W). A watt of power is available when one ampere of electricity passes through a pressure of one volt. Most of the time electric power is referred to in kilowatts (kW). A kilowatt is 1000 watts.
Generators can produce both alternating current (AC) and direct current (DC). With direct current, the electrons travel in only one direction. The electrons in an alternating current reverses direction at regular intervals. Transmitting direct current is much more difficult than transmitting alternating current. In the United States electric is supplied as an alternating current at 60 cycles per second or 60 hertz (hz).