The AlternateSyntaxParser Extension provides the ability to use alternate syntax engines (such as Markdown and Textile) instead of the standard wikitext parser.
This can be done (nicely/easily) on a page-by-page basis, or by setting a site-wide default.
The wiki markup is the syntax system you can use to format a Wikipedia page; please see Help:Editing for details on it, and Help:Wikitext examples for a longer list of the possibilities of Wikitext.
This tool (source code) converts the HTML table tags into their wiki equivalents, which were developed by Magnus Manske and are used in Wikipedia, the free encyclopedia, and all other wikis running on MediaWiki.
"MediaCloth is the first MediaWiki parser written in Ruby. MediaCloth is also the first true MediaWiki parser which has handwritten lexer, LALR parser, AST builder, walker and HTML generator."