By the end of the year 2000, an estimated 100 to 500 million computers may be linked to the Internet, representing an enormous level of information exchange. Even today, a broad Internet search of a term such as "breast cancer" can produce an overwhelming list of web pages, most of which will not be of interest to the typical Internet user. A more sophisticated user such as the oncology professional will more likely refine the search by adding other terms, producing a more manageable and useful list of websites. Information on cancer can be readily accessed from thousands of websites developed by the government, medical organizations, other institutions, medical journals, patient support groups, and pharmaceutical companies, as well as through medical web directories. The Cancer Information Network (CIN), an independent website geared to the oncology community, provides access to Medline, PDQ, and hundreds of cancer-related resources on the World Wide Web. CIN also offers the complete NCCN conference proceedings and practice guidelines; full text of several medical journals, textbooks, and handbooks; a daily oncology news service; a clinically oriented drug reference guide; and an extensive calendar of medical meetings and CME courses.