Markdown by DaringFireball - Text-to-HTML conversion tool/syntax for web writers, by John Gruber
mdbook - Gitbook alternative in Rust
GitHub Flavored Markdown - GitHub uses "GitHub Flavored Markdown," or GFM, across the site--in issues, comments, and...
MkDocs - Project documentation with Markdown.
Texy! - Texy! is a lightweight markup language as well as converter of this format to XHTML, in a form of a...
GitBook - Modern Publishing, Simply taking your books from ideas to finished, polished books.