Variorum: A Multimedia-Based Program Documentation System

Conventional software documentation systems are mostly based on textutal descriptions that explain or annotate the program's source code. Typically they also support interactive browsing of high-level control ows, and name-based searching of program primitives such as variable declarations and function deenitions. Because these systems rely solely on texts, it is diicult for program authors to describe overall algorithm structures and detailed implementation considerations of the programs in an interactive and exible fashion. Variorum is a novel software documentation system that allows program authors to record the process of \walking through" their own code using mul-timedia technology, speciically, text, audio, and digital pen drawing. This approach greatly improves the interactivity and exibility in the software documentation process. In addition, to broaden its applicability and to reduce the implementation complexity, Variorum is designed to inter-operate with the WWW technology, in that the program source code les and their annotations are stored on web servers and directly accessible via commercial web browsers such as Microsoft's Internet Explorer. This paper describes the design and implementation of Variorum, as well as preliminary usage and performance experiences with the current prototype.