Concept:
A capacitor is an electrical component that stores electrical energy in an electric field. It contains dielectric material between conducting plates.
Step 1: A capacitor consists of two conducting plates separated by a dielectric.
Step 2: When voltage is applied, charge accumulates on the plates.
Step 3: The dielectric between the plates undergoes polarization.
Step 4: This polarization helps the capacitor store electrical charge.
Therefore, the correct answer is:
\[
\boxed{\text{Capacitor}}
\]