Capacitor

A capacitor is a piece of an electrical circuit that can store electrical energy. It has two wires (called terminals or connectors) that allow it to join other pieces (components) of a circuit. It works rather like a spring, ‘squashing’ in electrical energy and letting it spring back out when needed. It stores energy by having an electrical charge applied to its terminals by other parts of the circuit, and the energy can return to the circuit when needed the same way

Capacitors come in all sizes and shapes. In a small circuit like a phone or a computer they are often tiny, the size of a pencil tip. When used for large electrical things they can be as big as a fridge.