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PLUS - Plan-based User Support Final Project Report

Frank Berger; Thomas Fehrle; Kristof Klöckner; Volker Schölles; Markus A. Thies; Wolfgang Wahlster
DFKI, DFKI Research Reports (RR), Vol. 93-15, 1993.


This paper presents the results of the project PLUS (Plan-based User Support). The overall objective of PLUS was the design and the implementation of a plan-based help system for applications that provide a graphical and direct-manipulative interface. The design of graphical user interfaces is based on the principle that "the user is always in control". This means the user is responsible for performing his tasks according to his own strategy. This leads to a great degree of flexibility in task execution as opposed, for instance, to menu-oriented user interfaces. Usually, neither a definite sequence of interactions nor a fixed number of actions are required to accomplish a specific task. In addition, modeless user interfaces allow to work on different tasks in parallel and to arbitrarily switch between them. Within the project PLUS we developed various help strategies, including graphical representation of the current interaction context, tutoring modes, and animated help, to support novice and occasional users during their work with applications that provide graphical user interfaces.