Thirty-seven World Wide Web (WWW) sites that are devoted to instruction in histology were compiled and organized into a digest. The sites were located using Netscape and two search engines (Lycos and HotBot). The scope and design of the sites were highly variable and the Web sites could be categorized as electronic manuals, syllabi atlases, image galleries and quizzes. Those listed in the digest can be used for teaching, learning and reviewing laboratory histology. To assist instructors and students in identifying those that are most likely to be useful to them, the topics, content and highlights of each were briefly reviewed.