Websites
Apple Developer
Find tools, documentation, sample code and resources for developing with Apple technologies.
Codecademy
Codecademy provides free interactive tutorials on HTML/CSS, JavaScript, jQuery, Python, Ruby, PHP and various APIs.
Eloquent JavaScript
Eloquent JavaScript is a book providing an introduction to the JavaScript programming language and programming in general. The book is available online for free and includes coding sandboxes.
Google Developers
Search for Google products, documentation, samples and more.
Mozilla Developer Network
The Mozilla Developer Network (MDN) provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and HTML5 Apps. It also documents Mozilla products, like Firefox OS.
MSDN- The Microsoft Developer's Network
Find resources for developers, such as tools, code samples and more on the Microsoft Developer Network.