Usually, capacitor (formerly known as condenser) can be indicated by its first letter C.

It has two definitions:

1, Capacitor is an electrical component for storing energy. Capacitors are widely used for blocking direct current while allowing alternating current to pass, coupling, bypassing, filtering, tuning circuits, transforming energy and so on in electronic circuits.

2, any two close electrical conductors (including lead) separated by a dielectric (insulator) conductors can form a capacitor.  

Capacitors Category:

 According to materials, sub-ceramic capacitors, electrolytic capacitors, polyester capacitors, and so on.

 According to voltage level, sub-low capacitance, high voltage capacitors(high voltage ceramic capacitors,ceramic disc capacitors ), etc.
 By applications. Sub-electronic capacitors, power capacitors ... ...

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