Interaction model

In the context of e-Learning, interactivity is defined as "function of input required by the learner while responding to the computer, the analysis of those responses by the computer, and the nature of the action by the computer."

There are two variables describing the interactivity of a given lesson: technology affordance and user freedom. Technology affordance, also known as manual operators, is the richness of the communication between the student and the instructor usually expressed in terms of the input and output channels. User freedom, on the other hand, is a function of the degree of freedom the learning system grants the student in influencing the presentation of the lesson.

Technology affordance in the e-Learning is a function of the capabilities of available computer I/O devices, having a tendency to evolve as new input and output devices become obtainable. There are five levels of technology affordance interactivity:

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