1. Codecademy.com – Learn to program in several different languages for free.
2. LearnStreet.com – Learn Javascpript, Ruby, and Python.
4. RailsForZombies.org – Learn Ruby on Rails by watching videos and completing the exercises.
5. CodeLearn.org – Learn Ruby on Rails by creating an app right in your browser.
6. RubyMonk.com – Free interactive tutorials to help you discover Ruby idioms.
7. TryRuby.org – Take 15 minutes to give Ruby a chance.
8. Learn-C.org – Free interactive tutorials to teach you the C programming language.
9. LearnJavaOnline.org – Learn the basics of Java.
10. LearnPython.org – Learn the basics of Python.
11. TryHaskell.org – Learn Haskell with free interactive lessons.
12. Try.jQuery.com – Get the basic building blocks of jQuery by completing challenges and earning badges.
13. SQLZoo.com – Interactive SQL tutorials complete with quizzes.
14. Try.Github.io – Learn Git in 15 minutes.
15. TeamTreehouse.com – Learn how to build websites and apps. Paid subscription required.