Wikipedia
MultiMarkdown
MultiMarkdown is a lightweight markup language created by Fletcher T. Penney and based on Markdown. It supports more export-formats and implements some added features currently not available with plain Markdown syntax.
It adds the following features to Markdown:
- footnotes
- tables
- citations and bibliography (works best in LaTeX using BibTeX)
- math support
- automatic cross-referencing ability
- smart typography, with support for multiple languages
- image attributes
- table and image captions
- definition lists
- glossary entries (LaTeX only)
- document metadata (e.g. title, author, date, etc.)