I found this Hulu.com documentary on black holes that mentions relativity and how light and time bend in response to the gravitational pull of the black hole.
I found this article on relativity, which describes how light is a constant speed in a vacuum, such as space, and is a physical boundary of motion for objects. That is, it is not possible to move faster than the speed of light.
For humans viewing something moving at the speed of light, we perceive that something moving much slower than it really is – which makes sense if you consider that an airplane flying far away in the sky appears to be moving quite slowly when we logically know it’s moving quite fast.