Capacitors

Capacitors are devices used to store an electrical charge. Capacitors come in different shapes and sizes, but the most common type is a cylindrical container with an electrode at one end and a metal foil or wire mesh at the other. When you put an electric current through a capacitor, it causes the charge to build up on the electrode. When you apply a voltage across the capacitor, it will store this charge until the current is switched off. As long as there is a voltage across the capacitor, the charge will remain in it. There are two types of capacitors, those that store and release energy and those that store and change the direction of energy.