sometimes a great photo is about beautiful light, sometimes it's about good composition, but more importantly, the best photograph is the one where the photographer pushes the button at the right time. it's become such an overused saying, but cartier-bresson called it "the decisive moment".

if you can get all 3 of them in the same picture, then you've really got something

check here for "good" photography: http://www.magnumphotos.com/Archive/...d=2K7O3R1VX08V