The U.S. Patent and Trademark Office at www.uspto.gov includes information about patent and trademark laws, regulations, rules, fees, and application forms. The Cornell Law School's Legal Information Institute contains a complete collection of information on patent law (wwwsecure.law.cornell.edu/topics/patent.html) and trademark law (wwwsecure.law.cornell.edu/topics/trademark.html). If you do not understand the differences among patents, trademarks, and copyright, then read Intellectual Property: The Practical and Legal Fundamentals at www.fplc.edu/tfield/pLfip.htm. (Patent, Trademark, Copyright--What's the Difference at www.wigman.com/art07.htm is no longer available.) A very complete and well-organized index to patent resources on the Internet is The PNGV Patent Portal at www.ta.doc.gov/pngv/patent/pat-frm.htm. The Patent Resource Center at Derwent Scientific and Patent Information, www.derwent.com, contains an overview and history of patents, a showcase of historically significant patents, a glossary of terms, and a patent news index.