Access selected resources in a variety of topic areas; check out these tip sheets on where to go for the best Web resources in a variety of topic areas. I've selected 5 Web sites in 20 categories to give you a headstart on finding useful resources on the Web. I chose Web sites based on usefulness, usability, and depth and breadth of coverage. My goal here is not to present an exhaustive subject tree of all Web resources (see subject resources for those), but to give you a handful of Web sites in each of these categories representing the best of the Web. Reviews here are my opinion and are subject to change; if you know of a better resource to replace an entry in one of these lists, please let me know.