The extraordinary growth of the World Wide Web has been fueled by the ability it gives authors to easily and cheaply distribute electronic documents to an international audience. As Web documents have become larger and more complex, however, Web content providers have begun to experience the limitations of a medium that does not provide the extensibility, structure, and data checking needed for large-scale commercial publishing. The ability of Java applets to embed powerful data manipulation capabilities in Web clients makes even clearer the limitations of current methods for the transmittal of document data.-The extraordinary growth of the World Wide Web has been fueled by the ability it gives autho rs to easily and cheaply distribute electronic documents to an international audience. As Web documents have become larger and more complex. however, Web content providers have begun to experience the limitations of a medium that does not provid e the extensibility, structure, checking and data needed for large-scale comme rcial publishing. The ability of Java applets t o embed powerful data manipulation capabiliti es in Web clients makes even clearer the limitat ions of current methods for the transmittal of d ocument data.