I think the point is something like this: Assembly is the only language your machine can run. Everything else your machine does must eventually be converted t

I think the point is something like this: Assembly is the only language your machine can run. Everything else your machine does must eventually be converted to a machine instruction. Javascript is the only client side DOM manipulation scripting language that all browsers can run. Everything else (CoffeeScript, for example) must eventually be converted to javascript. I think that is the core of the analogy, and it is not talking about how high or low level each language is in an absolute sense but in a relative sense. It is talking about it being the "at the metal" language of machine instructions and browser "instructions" respectively. Of course, there are other parallels, but they aren't as strong. Part of the reason for using CoffeeScript is because of a perceived increase in expressiveness, but that increase is very small compared to the improvement of C over assembly (as the author of this article points out).