Capacitor is made of two conductors separated by an insulating dielectric. When a potential difference is applied, an electric field is created and charges are stored. Once the potential difference is removed and the conductors are connected, the stored charges flow in a current to neutralize the potential difference and electric field. The rate of discharge decreases over time in a known capacitor discharging curve. Capacitors act as insulators for direct current but conduct alternating current, so they are used as direct current blocking elements in circuit designs.