It is well-accepted that learnability is an important aspect of usability, yet there is little agreement as to how learnability should be defined, measured, and evaluated. In this paper, we present a survey of the previous definitions, metrics, and evaluation methodologies which have been used for software learnability. Our survey of evaluation methodologies leads us to a new question-suggestion protocol, which, in a user study, was shown to expose a significantly higher number of learnability issues in comparison to a more traditional think-aloud protocol. Based on the issues identified in our study, we present a classification system of learnability issues, and demonstrate how these categories can lead to guidelines for addressing the associated challenges.
The Learning project aims to investigate advanced techniques for assisting users in learning complicated applications. We are interested in a range of investigations from the scientific study of the human learning process to prototyping novel interaction techniques for improving the general learning mechanisms that can be applied to all applications.