In many classroom settings, teachers provide prepared slides or notes to the students before a lecture, and many students consider this to be an advantage. In addition, many of the other tasks we perform in our daily lives are annotation tasks. Drafts of a paper are frequently annotated by reviewers, and a teacher corrects a student's report by annotating it. Support for annotation is useful for the classroom and other settings.
Annotation is simplified when the underlying image -- such as a slide used the presentation-style lecture -- does not change. This approach does not work for all lecture styles. It would be better to have prepared material for presentations that differed in form or content from the material used for review. The material for presentation must be readable when projected and fairly terse, as reading lots of text off a wall display is not effective. The material for review should be more like a user-modifiable textbook, suitable for a personal display and containing more explanations.
Future Computing Environments