They're not the only players in the MOOC market, but whether because of high-profile founders, big funding or broad reach, they're the three biggest. So how do EdX, Coursera and Udacity stack up against each other?
None of the companies is public, so hard numbers can be difficult to come by. But here’s a snapshot of each, including a short summary of each player and where each stands by the numbers in terms of funding and course enrollment, along with key partnerships and big news (good and bad) this year.
Backstory: Alone among the top three players, EdX is a nonprofit. Based in Cambridge, Mass., it was founded and is jointly governed by MIT and Harvard.
Founded: May 2012
Technology: Open-source platform
Number of participating institutions: 28 (dubbed the xConsortium)
Number of courses: About 60
Course enrollment: 1 million registered users as of June
High-profile partnerships: Co-founders MIT and Harvard, plus Berkeley and Cornell
Big news this year: In February, EdX doubled its university partners and expanded abroad. In May, it happened again.
Backstory: Started by two computer science professors at Stanford University, Coursera was inspired by co-founder Andrew Ng's observation that his course material on YouTube had many more views than there were students in his class.
Founded: 2011 (public launch in April 2012)
Technology: Proprietary platform to which schools contribute their own content
Number of participating institutions: More than 80 institutions listed
Number of courses: About 400
Course enrollment: More than 4 million students
High-profile partnerships: Yale, Northwestern and Stanford
Funding: $65 million in funding (after a $43 million round in July)
Backstory: Udacity emerged from a Stanford University experiment in which Sebastian Thrun and Peter Norvig put their class on artificial intelligence online for the taking. The response was huge. Thrun is the inventor of Google's self-driving car and one of the forces behind Google Glass.
Founded: February 2012
Technology: Unlike EdX and Coursera, Udacity produces courses in its own studio, rather than distributing content created by universities.
Number of participating institutions: Courses are taught by faculty from at least 5 universities, plus private partner companies such as Google, NVIDIA, Microsoft and Autodesk.
Number of courses: About 30
Course enrollment: More than 750,000 as of late last year, with the number of courses doubled since then
High-profile partnerships: Georgia Tech, San Jose State (see "big news this year" below)
Funding: As of late last year, the company had raised $21.1 million in capital, including $15 million in October.
Big news this year: The headlines for Udacity have been a mixed bag this year. In January, there was the triumph of signing San Jose State as a partner, with a for-credit course experiment in the offing. In July, that partnership was put on pause. Georgia Tech's decision to partner with Udacity for an online master's degree also made a splash.
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