One point of MOOCs is that they are not text books. That does not mean text books are bad or that MOOCs are all you'll ever want.
Some MOOCs create video content totally "from scratch", but usually they build on the lecturers' ability to hold a lecture in the topic, often honed through years of repeated lecturing on the same topic.
Some MOOCs create video content totally "from scratch", but usually they build on the lecturers' ability to hold a lecture in the topic, often honed through years of repeated lecturing on the same topic.