I KNOW WHAT CAPACITOR IS. IT'S AN EQUIPMENT THAT SAVES ELECTRICAL ENERGY. MY QUESTION IS THIS: LET'S IMAGINE WE HAVE A CIRCUIT : BATTERY, A LIGHT, AND CAPACITOR. CURRENT FLOWS THROUGH ALL OF THEM. CAPACITOR IS TRYING TO SAVE ENERGY,ITS VOLTAGE IS INCREASING, AND FINALLY, WHEN IT'S FULLY CHARGED, A LIGHT gets switched off. then,when this all happened, question is why did we use capacitor? what did it help us with? maybe I didn't want light to be switched off, but let's say I wanted it, then looking at this condition, what am i gonna do with capacitor that has energy now?