Learn Markdown in 60 pages. The Markdown Guide book includes everything you need to get started and master Markdown syntax.| www.markdownguide.org
W3C i18n tutorial: What you need to know about character encodings and characters in HTML and CSS.| www.w3.org
MultiMarkdown| fletcherpenney.net
Advanced features that build on the basic Markdown syntax.| www.markdownguide.org
The Markdown elements outlined in the original design document.| www.markdownguide.org
GitHub Flavored Markdown Spec| github.github.com