Basically just started reading up on the theory of relativity and physics in general in the last few weeks, so I am a self confessed novice in all things science. I have a few questions about light which I have so far been unable to find any direct answers to. 1.) If light has no mass or weight, how can I see it ? 2.) What force makes light travel forward ? 3.) Why does it always travel at a set speed ? Why is this set speed 299 792 458 m / s and not some other random number ? I know I sound like a 3 year old asking why is the sky blue, but that is where I am at. Cheers.