A good place to mention what's out there regarding topic maps is right up front. Here is a brief listing of important Web sites. (Keep in mind that Web site addresses change from time to time.) After this list of resources, we'll talk more about what's in this book.
 This list is not intended to be complete. Resources will be updated periodically at the book's official Web site: http://www.nexist.org. The Web being what it is, however, you should always be ready to use a good search engine.
http://www.topicmaps.org— the original XTM Web site.
http://www.topicmaps.net— a Web site created by Michel Biezunski and Steven Newcomb.
http://easytopicmaps.com— a WikiWiki (Hawaiian for “quick”) Web site devoted to topic ...