HTML CSS

HTML5

• HTML5 Rocks

• HTML5 Bible

• Semantic HTML (HTML5).

• Browser Compliance: Up to date info on browser manufacturers compliance with HTML5 & CSS3 standards, and a couple others.

HTML - General

• QuirksMode - Browser Compatibility
• HTML URL Encoding Reference

CSS - General

• CSS Reset: IMHO, good to include if you want to 'reset' the default styles of whatever browser a user happens to be using when they see your site.

Clean Css: CLean up your CSS after you've finished it. (Use with care)