A MOOC should be able to accommodate a large or very large number of learners compared to what is possible in a typical university classroom or online course. A MOOC also requires significant investment in infrastructure and support processes to scale. An online course will not necessarily be built that way. Scalability is the distinctive feature that makes a MOOC different from a conventional online course.
Open universities that offer online courses often include personalised feedback and assessment as part of the offering. In a MOOC, personalised feedback ordinarily is not expected—another difference between conventional online learning and MOOCs. A further difference tends to be price. MOOCs are (mostly) free, whereas online courses are (mostly) paid for as part of a student’s programme of instruction through an institution’s programme or course registration fees.