So what is a "passive component"? I guess, a water wheel that drives a pump that pupms water way above the surface level would count as active? What about a ma

So what is a "passive component"? I guess, a water wheel that drives a pump that pupms water way above the surface level would count as active? What about a material that absorbs photons and emitts them at a higher energy level (emitting one after absorbing two)?