Web Design & Web Development

HTML: The Markup Language Editor's Draft (i.e. under development)
Written for web content producers and editors, this non-normative W3C document provides a quick, yet through reference for the complete set of HTML5 tags. Tags and attributes introduced or modified since the previous version specification are clearly marked. Pages for individual tags are structured with essential quick-reference information at the top with in-page links to specific details, including data types.
The HTML5 Test
Learn how well (or poorly) the major web browsers support features introduced in HTML5, and test your browser. Test results include statistics for a variety of smart phone, tablet, and media center browsers as well as the traditional lineup of desktop browsers.
Web Content Accessibility
Web Content Accessibility Guidelines
An overview of the standard from the W3 Consortium.
Functional Accessibility Evaluator
An online accessibility testing tool from the University of Illinois at Urbana/Champaign