A capacitor is constructed of two conductors (plates) separated by a dielectric.
A capacitor will store energy in the form of an electric field caused by the attraction of the positively-charged particles in one plate to the negatively charged particles in the other plate.
The attraction of charges in the opposite plates of a capacitor opposes a change in voltage across the capacitor.
Capacitors in series are combined like resistors in parallel.
Capacitors in parallel are combined like resistors in series.
The capacitive time constant is the time required for the capacitor to charge (or discharge) to 63.2 percent of its fully charged voltage.