Notes is a hypertext application developed to investigate the effects of computers on the writing process, in particular, on the processes of acquiring and structuring knowledge when writing from source texts. Notes is designed to help writers record their own ideas (e.g., reactions, inferences, plausibility assessments), recover the context for those ideas easily and view ideas from multiple perspectives. In this paper we outline the theoretical basis for the design of the Notes program. Then we briefly describe the program itself and its relation to relevant research. Finally we describe our experience with users.