This question already has an answer here:
The way things are explained, is that light is just the same as electromagnetic radiation I thought this would be strange as then microwaves and radios would also be called light. Plus, I am not sure of the origin of the word photon, but in Japanese which I use it is 光子 which kind of translates to light molecule.
I found an answer to this:
electromagnetic radiation to which the organs of sight react, ranging in wavelength from about 400 to 700 nm (http://dictionary.reference.com/browse/light?s=t)
However, after searching the web it seems that this is approximately the same spectrum for humans. So, is there a difference between light and visible light? If not, why use visible light?