Design Issues for Line-Driven Text Editing / Annotation Systems

Recent research on interfaces driven by line-markings indicates that there are many potential benefits and applications of such interfaces. Benefits include the exploitation of users' handwriting skills and their skills in understanding handwritten marks. There are systems that have exploited one or the other of these benefits but not both. One application which would take advantage of both of these benefits is asynchronous collaborative text editing. In such an application, line-markings could be used for specifying commands, thereby taking advantage of users' hand writing skills, and for creating explanatory notes or annotations, thereby exploiting the users' understanding of handwritten marks. But there are many unknown and unsolved issues in designing such an application and for line-mark driven systems in general. This paper examines some of these issues in the context of an asynchronous collaborative text editing system. This system, termed MATE for Mark-up Annotator / Text Editor, is currently being designed and implemented.