htmlreference.io - Learn by example with this free web-based guide to HTML.
The Little Book on CoffeeScript - "The Little Book on CoffeeScript" is a short (62 page) book that shows developers how to build web applications with CoffeeScript.
W3Schools - W3Schools is a web developers information website, with tutorials and references on web development...
Smooth CoffeeScript - Learning Resources
CSS Reference - Sleek and comprehensive online reference for CSS
Exercism.io - Download and solve practice problems in over 30 different languages.