User interface aspects of an intelligent tutoring system

Intelligent tutoring systems (ITTSs) are a class of computer systems allowing human teacher emulation in the process of learning and teaching. From the user´s standpoint most of an ITS can be considered as a user interface, since it brings ITS functionality to mostly non-technical users. This is the main reason why in designing an ITS human-computer interaction becomes one of the most important issues. In the paper an intelligent authoring shell, which is an ITS generator, is described and its user interface aspects discussed. This authoring shell, which is named Tutor-Expert System (TEx-Sys), is parameterized with domain knowledge and used in teaching at the university and secondary school level.