Light (both natural and otherwise) is an essential tool in photography - here's a gallery dedicated to light use in photos, including low-light photography, black and white available light photos, night and morning photos.
Looking For The Muskrat
© Michelle CampbellSundown at Golden Gate
© Kerry DragerMS-1478
© Jim ZuckermanA quiet moment
© Kathy HarrisLife, Liberty and the Pursuit of Happiness
© Patricia MarroquinPractice Makes Perfect
© Michelle Campbell