Pretty much. Capacitors are used to store energy, which is just about the same as power (unless you're a physicist - they get picky about stuff like that :). They're basically used for two sorts of things: 1) temporary storage of electrical energy - for example, to keep volatile memory from being wiped while a portables device's batteries are being changed. 2) on AC (alternating current) circuits, capacitors can be placed so as to "condition" the alternating character of the current - just when the alternation takes place, and how fast, and stuff like that. This conditioning helps the electrical engineers get the right amount of power to the right place at the right time. Just how and why this conditioning works is beyond me - I never got all that far with AC circuitry. But I do know that it's essential to things like Los Angeles sending power to heat Seattle homes in the winter and Seattle sending LA power to run air conditioners in the summer, or me being able to pick up the phone in Seattle and use a system based on electric signals to talk to my friends in LA. Hope this helps.