MultiMarkdown, or MMD, is a tool to help turn minimally marked-up plain text into well formatted documents, including HTML, PDF (by way of LaTeX), OPML, or OpenDocument (specifically, Flat OpenDocument or ‘.fodt’, which can in turn be converted into RTF, Microsoft Word, or virtually any other word-processing format).
MultiMarkdown, or MMD, is a tool to help turn minimally marked-up plain text into well formatted documents, including HTML, PDF (by way of LaTeX), OPML, or OpenDocument (specifically, Flat OpenDocument or ‘.fodt’, which can in turn be converted into RTF, Microsoft Word, or virtually any other word-processing format).
MMD is a superset of the Markdown syntax, originally created by John Gruber. It adds multiple syntax features (tables, footnotes, and citations, to name a few), in addition to the various output formats listed above (Markdown only creates HTML). Additionally, it builds in “smart” typography for various languages (proper left- and right-sided quotes, for example).
MultiMarkdown was originally a fork of the Markdown Perl code, but as of version 3.0 has been rewritten as a fork of peg-markdown by John MacFarlane, written in C. It can be compiled for any major operating system, and as a native binary runs much faster than the Perl version it replaces. Many thanks to John for creating a great program, and sharing the source with the github community. MultiMarkdown 3.0 would not be possible without his efforts!
Attribution to fletcherpenny.net for this well written definition of MultiMarkdown.