To add to this, ASA values correspond to the size of the silver halide grains that are "exposed" when light hits the emulsion layer. Lower ASA values mean finer grains and sharper images, provided correct focusing and such are used. However, fine-grain stock (<200 ASA) will be less sensitive to light than, say, 400 ASA stock. You will have to compensate somehow, artificial light or whatnot, if you're looking for "correct" exposures. Another thing to take note of is exposure latitude, which is typically higher with faster stocks, giving more contrast.
That is not to say that you can't bend these rules for artistic purposes, but it would be better to know these things in order to exploit them later on.
Since the transition from video to film introduces many new concepts, you would do well to do a lot of your own research. There are endless amounts of literature on the internet and in books and it doesn't matter, at least in the beginning, where your info comes from. Just be voracious in your acquisition of it. Traditional photography books are good resources to help you get acquainted with the behavior of film. I'd actually recommend possibly getting into still photography as well to familiarize yourself with film, but you don't have to really... the aforementioned books would at the very least hit you with the basics of exposure, depth of field, and the rest.
Good luck!
