Udemy is a brand new website specializing in offering free and paid learning courses.
Udemy’s course topics vary from music theory to web app development and entrepreneurship. There are myriad courses for any taste.
Among learning websites like duolingo and Khan Academy, Udemy is perhaps the best-developed and with most content, as experts can actually sell courses they’ve created.
Try it! Maybe have a look at Mobile Apps Development, iPhone App Making, or even MySQL Database For Beginners. They’re all free, of course.