This is a rather stupid question I guess, but anyways:
From all what I've read, the difference between per-pixel lighting and per-vertex lighting is that the first is calculated per-pixel (sounds rather logical), speaking in the pixel shader.
Well, if this is right, are the shaders from the shader tutorial using per-pixel lighting then? If so, I understood it, if not, well, then I'm lost. Hope this question isn't too dumb.