A capacitor is an electrical device that can store energy in the electric field between a pair of closely spaced conductors (called 'plates').
When voltage is applied to the capacitor, electric charges of equal magnitude, but opposite polarity, build up on each plate.
Capacitors are used in electrical circuits as energy-storage devices.
They can also be used to differentiate between high-frequency and low-frequency signals and this makes them useful in electronic filters..
For more information about the topic Capacitor, read the full article at Wikipedia.org, or see the following related articles:
Note: This page refers to an article that is licensed under the GNU Free Documentation License. It uses material from the article Capacitor at Wikipedia.org. See the Wikipedia copyright page for more details.

