Every MOOC is different, but the "Networks Illustrated: Principles without Calculus" course offered by Princeton is pretty representative of the university version. It is a six-week, not-for-credit course offering free, unlimited enrollment without prerequisite knowledge, using student-to-student and instructor-to-student interaction models, and mostly automated feedback on coursework [sources: Coursera, Brinton]. While the course itself is free, the suggested reading for the course is not; students who want to read the recommended book have to purchase it.
Christopher Brinton, a Princeton Ph.D. candidate (in 2013) in electrical engineering (EE), and Princeton EE professor Mung Chiang teach the course primarily via prerecorded video lectures, which is the norm. They present two one-hour lectures per week, with multiple-choice, instant-feedback quizzes interspersed throughout to test comprehension. Instructors answer students' questions regularly via forum and occasionally in live chat sessions, or "virtual office hours" [source: Brinton].
Coursework is estimated to take six to eight hours per week, with weekly homework assignments and midterm and final exams. All are multiple-choice, machine-graded, and provide instant feedback and explanations. With no reliable oversight to prevent cheating, Princeton does not offer course credit, a final grade or a certificate of completion. Since this particular course is not job-skill oriented, "I find it fascinating that still around 100,000 students have enrolled ... in the first year," says Brinton.
This is a common framework, but it's not universal. The pre-calculus algebra course offered by Ball State University includes peer assessment of coursework [source: Canvas]. The not-for-profit organization Open Security Training's MOOC on rootkits is self-paced, meaning anyone can start and finish the course at any time. That course has recommended (but not required) prerequisite knowledge bases; all suggested course materials are free [source: MOOC List].
North Carolina (NC) State University offers an "upgrade" option for its MOOC course Digital ASIC Design that makes it possible to receive college credit. Upon completion with a grade of 80 or above, a student can enroll in NC State as a non-degree-seeking student, successfully complete a few additional, proctored and/or human-graded assignments, and receive full credit for the class [source: MOOC List].
The number of students taking advantage of all these MOOCs is in the millions [source: Allard]. Only about 10 percent complete the courses, though – and, depending on who you ask, that's not necessarily a bad thing [source: Simonite].