EXPERIENCES WITH SEMANTIC NET BASED HYPERMEDIA

The Many Using and Creating Hypermedia (MUCH) systems is based on the Dexter model and treats the storage layer as a semantic net. The MUCH system provides a number of recommended link types for representing ap plication domain concepts, such as thesauri, documents, and annotation s. Users of the system are expected to use those link types in the cou rse of authoring meaningful hypermedia. This paper is based on the log s of usage of the MUCH system over 2 years by over 200 people. Contrar y to the expectations of the buliders of the MUCH system, the users di d not exploit the ability to type semantic links. Typically authors us ed the default link type regardless of their semantic intentions. When a link type other than the default type was chosen, that choice was o ften inconsistent with the way another user would label a similar link . The system has proven to be useful for authoring conventional docume nts. Authors, however, were not practically able to produce hypertext documents. Based on these experiences a new system, RICH (Reusable Int elligent Collaborative Hypermedia), has been designed and built which emphasizes rules for typing links and maintaining the integrity of the semantic net. (C) 1995 Academic Press Limited