there's never anything ever dumb about wanting to learn something to better yourself, and don't believe anyone who tells you any different. C is VERY widely used, the only thing with it is that a lot of the programs that still use it are legacy. Not like that's a problem, but if you want to learn it you'll want to learn ANSI C because that'll likely be the lowest common denominator for C wherever you go. I mean you could learn K&R C, but really I don't think you need to do that unless you know that you'll need it.