In the last three years we've witnessed an explosion. From an initial three free online computer science courses there are now over a hundred to choose from and keeping up with them all is an increasingly difficult juggling task. Luckily there are websites to help.

Turn the clock back to August 2011 and we ran a news item announcing Introduction to Artificial Intelligence, the online version of a Stanford class to be taught by Sebastian Thrun and Peter Norvig.  Later in the month we had news of two more free online courses from Stanford,  Professor Andrew Ng's Machine Learning Course and Professor Jennifer Widom's Introduction to Databases.

The idea of a MOOC wasn't new, but it wasn't a term that was in common parlance. It quickly became so commonplace that last year it was added to the Oxford Online Dictionary. Something else that came as a shock was that something so useful and valuable was being provided completely free. Again this wasn't new - Andrew Ng's course had been on You Tube since 2008 and MIT's OpenCourseware with free university-level course content was already well established, but the Fall 2011 classes marked a step change in terms of the number of participants and the degree of interactivity and engagement.

These courses are now viewed as the three inaugural massive open online courses (MOOCs) that were the start of a disruptive change. The experience of attracting students in huge numbers from around the world led Sebastian Thrun to embark on Udacity and Andrew Ng and Daphne Koller to found Coursera. The list of providers has since expanded with edX offering courses from elite US universities, FutureLearn encompassing the UK's Open University plus other universities across the world, Open2Study with short "taster" courses from Austrailian Universities, iversity based in Europe and many more.

As this graph (compiled by Class Central) shows the number of MOOCs on offer is growing exponentially - and the graph only shows MOOCs that have start dates - there are many more whose datas are "to be announced".

I Programmer has been (and will continue to be) an enthusiastic proponent of this educational model but with so many Computer Science MOOCs, not to mention those in other subjects, it is increasingly difficult to do justice to them all. So this article is not about specific MOOCs, or MOOC providers, but about MOOC finders.

Class Central

The resource I've relied on longest for finding relevant courses is Class Central. Since it started in 2011 it has expanded from listing just Stanford's online offerings to those from an extensive and comprehensive list of providers. Although its home page makes it look as though it is limited to universities its list of 400 institutions encompasses Udacity, Canvas.net and Udemy.

Class Central currently lists 283 Computer Science courses but some of these are finished and may never be re-run. To assist search you can choose courses that are in progress, recently announced or about to start. You can then choose one or more areas of study, including Computer Science for a list of options. It has ratings and reviews for some of the courses it lists, but these are in the minority.

An alternative way to find courses is to enter a keyword in its search box for a drop down list of options.

For Class Central's signed in members, it has a MOOC Tracker. This lets you build your own catalog of courses under the headings including “Interested”, “Enrolled”, “Partially Completed”,”Dropped” and you'll be notified when a course in your catalog is about to start or is offered again. You can also use keywords, for example a topic such as Python or Game Development or the name of a specific provider, to search the course catalog and can then filter the list by Start Date and subject area.