Humor writing can take many forms, Michelle. On this board alone, I know there are individuals who have been paid to write family/parenting humor (think the back pages of Family Circle and similar magazines), greeting cards, jokes for comedians, satire, and there's even one author in our ranks with a fishing book that claims to be at least partially humorous (I think it has jokes in it about the one that got away, but I'm not certain if that's from the fisherman's or the fish's point of view). And then there are those individuals use humor as a tool in otherwise serious works of fiction and non-fiction.
You might get a better response to this question in the humor forum. If you'd like, I can move this thread for you. Just let me know.