Getting back to the basic levels of interactivity, I found it hard to understand it, even after reading until I read an article on ineractive-pioneers.org. It explained it in a way that would help you understand the vocabulary and the uses of interactivity. The most basic level can be compared to a lecture. Each audience member sets the pace of the presentation in multiple media. The lecturer accepts no input from the audience except for when to turn the page. So, in our context the computer is an expensive page turner. In the medium level the user can choose multiple paths through subject matter. An example of this is multimedia encyclopedias, it does not teach, it provides an environment where people can easily locate and manage information. In the highest level of interactivity the program can present an electronic simulation of an environment and prompt the user to respond to simulated conditions with tools. So, what I got from all of this is that interactivity is your interactions with media. Every level is how much interaction takes place with you and the medium. To comment on Curtis’ post about the interaction with the stairs, I also saw a video by the same company with an interaction with a trash can. When you threw something in the trash can it made a noise. This is the lowest level of interactivity.