- Eric Weisstein's World of Mathematics - Bibliographic dictionary of almost 10,000 mathematical terms. Material ranges from undergraduate to research level.
- Frequently Asked Questions in Mathematics - Covers diverse topics such as algebra structure, names for large numbers, how to compute pi and games.
- Glossary of Math Terms - Explains commonly used words specialized to this field. Includes examples and some graph illustrations.
- Knot a Braid of Links - Award/review service for other math web sites and web pages, with a new selection each week.
- Mathematics Archives - Combined archive and directory of mathematics web sites, mailing lists, and teaching materials. At University of Tennessee.
- The Math Forum - Combined archive and portal to web resources, educational issues, help forums, mailing lists, and teaching materials.
- The Mathematical Atlas - Dave Rusin's survey of research-level mathematics, with introductory articles for non-mathematicians and hyperlinked bibliographies in each of dozens of research areas.