Direct current or DC is electricity that directly
flows through a conductor, such as a metal wire. This is different
than static electricity, which typically collects on the surface of
a non-conductor such as a piece of plastic. It is also different
than alternating current (AC) electricity, which flows
back-and-forth in a conductor. You usually get DC from batteries,
although DC generators are another source of this form of
electricity. The characteristics of DC electricity in a circuit are
voltage, current and resistance. DC is used to power some devices,
but it is not usually used as home electricity.
