Looks well written, but it seems undecided on whether it's targeting experienced programmers or newcomers. I have to disagree with priyatham_'s position that it effectively targets both.
The Loops section gives a very brief description of what loops are. This doesn't introduce anything of value to an experienced programmer, and it's nowhere near enough of an explanation for teaching imperative programming to a beginner.
Personally I'd suggest targeting experienced programmers. I only learnt JavaScript relatively recently, and I found it very frustrating that every JavaScript tutorial I could find was aimed at beginners (and that isn't an exaggeration).
The Loops section gives a very brief description of what loops are. This doesn't introduce anything of value to an experienced programmer, and it's nowhere near enough of an explanation for teaching imperative programming to a beginner.
Personally I'd suggest targeting experienced programmers. I only learnt JavaScript relatively recently, and I found it very frustrating that every JavaScript tutorial I could find was aimed at beginners (and that isn't an exaggeration).