Founded in 2012, Coursera has grown into a major for-profit educational-technology company that has offered more than 1,000 courses from 119 institutions. While you can pay for certain programs to receive a certificate, there are a number of free introductory programming courses in various specializations from universities such as the University of Washington, Stanford, the University of Toronto and Vanderbilt.
Codewars adds some quirk to the proceedings by offering free coding classes with a martial arts theme. Solving specific coding “katas” (a term for training exercises in karate) will earn you ranks and honors as you move your way to becoming a bonafide coder. Who said learning to code online couldn’t be fun? Codewars also offers one of the more diverse lists of programming languages. Choose free coding classes on: