### Scott

* _"Essentially we made a function that takes a two dimensional vector (x and y) and returns a four dimensional vector (r, g, b and a)."_ Really?  Are you sure that’s what we did?

* What is smoothstep()?  This example starts to lose me.  There are many new elements here.  Could you include a step by step walkthrough of this whole example before proceeding to the next part?

* Actually, this is the point where you lose me. I want it to be more gradual.  It feels like there are 100 new concepts on this one page.
