Kent defines distance learning as interactive television which may or may not involve students actively and may or may not be computer mediated. The third in the series, the web, was thrown in I suspect as a misnamed afterthought portmanteau category to represent for all other forms of computer mediated teaching. Distributed learning is in experimental stages. Imagine linked computer classrooms, each computer equipped with individual audiovision cameras. Students see the instructor as a television picture on a small portion of their screens and hear through headsets, even when the students are at the originating site.
All interaction is computer mediated or electronically transmitted voice.
Carefully planned classes use multimedia presentation and require students to use the keyboard and mouse to perform tasks. Distance learning is the most familiar method for offering courses at multiple sites. Kent's argument is that distance learning is best suited to traditional lecture presentations and is more difficult to use for active student involvement than distributed learning software. Distance learning is not, by this definition, on line, so this is the last time I'll mention it. And finally, the portmanteau category.