A capacitor is capable of storing energy in the form of an electrostatic field. This is done by having two metal plates separated by an insulating material, such as a dielectric. When a voltage source is connected to the capacitor, it stores a charge on each plate. This charge creates an electric field between the plates, and this field stores the energy and holds the charge on the plates.
Capacitance is the ratio of an electric charge to the electric potential difference between two conductors. Capacitance is a measure of a material’s ability to store an electric charge. It is measured in Farads (F), which is equal to one Coulomb of charge per Volt of potential difference.