Sorry folks, I couldn't find the "newb" section for this undoubtedly stupid question. I started reading the wikipedia article on photons, and it states that a photon is massless. My understanding was that all light is photons, but also that light is affected by gravity. It was also my understanding that gravity only affects things with mass.. so I'm confused about how, say, a black hole, would bend light. Could someone lay this bag of snakes out straight for a physics dummy? Thanks!