This lecture platform works by allowing groups of users to create slides and presentation, but at the same time also define a transcription of it.
It is all done in markdown however, to avoid the tendency for users to fiddle around with styling.
Along with each slide, a speaking script is provided, which is read via TTS (text to speech) alongside with the slides.
This allows for students to use the lecture, and provide actual feedback by pushing suggestion for modifications to the text to speech script
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With a more powerful semantic markup, you could allow for variable complexity for the slides. Changing the lecturer from a short summary, to a hyper detailed explanation at a click of a button.-- mofosyne, Oct 03 2014 Not a single military figure involved...tch.-- not_morrison_rm, Oct 03 2014 My commendations.-- normzone, Oct 03 2014 random, halfbakery