&what: Discover Unicode & HTML Character Entities : amp-what is a quick, interactive reference of 14,500 HTML character entities* and common Unicode characters, 8859-1 characters, quotation marks, punct...
Email Standards Project : The Email Standards Project is about working with email client developers and the design community to improve web standards support and accessibility ...
AlsacréationS : Alsacréations est une communauté dédiée à l'apprentissage des standards web (W3C, HTML, XHTML, CSS) ainsi qu'à l'accessibilité numérique
Explorer Exposed! : These CSS bugs are all found only in Internet Explorer, versions 5 and higher. To see the demos properly, they must be viewed in IE, of course.
This site provides a collection of schemas that webmasters can use to markup HTML pages in ways recognized by major search providers, and that can also be used for structured data interoperability (e.g. in JSON).
CSSdoc : This is a draft to bring automatic documentation to CSS files, like its known for JavaScript and PHP files through JavaDoc/DocTags.
Ionic : The beautiful, open source front-end SDK for developing hybrid mobile apps with HTML5.
Impel : Impel takes the pain out of working with HTML5 asynchronous databases.
Statement callbacks? Transaction callbacks? One-to-many and many-to-many relati...
TLDR pages : The TLDR pages are a community effort to simplify the beloved man pages with practical examples.
Codelabs management & hosting tools : Codelabs are interactive instructional tutorials, which can be authored in Google Docs using some simple formatting conventions. You can also author c...