The capacitor is an elementary electronic component, made up of two conductive surfaces called "electrodes" that are charged equally but oppositely and separated by a polarizable insulator. Its main property is to be able to store opposite electrical charges on the surface of each electrode plate. The capacitor is mainly used to stabilize power supply (it discharges during voltage drops and charges during voltage peaks), to process periodic signals (filtering, etc.), to separate alternating the current from the direct current, to store electric energy, in which case we call it a supercapacitor. Film capacitors, as well as ceramic capacitors and electrolytic capacitors are the most common types of capacitors used in electronic equipment, and are found in many AC and DC microelectronic and electronic circuits. Electrolytic capacitors will be recommended when a large storage capacity is required.