A WikiLink is a phrase within the wiki that links to either a document within the wiki, a section within a document, or to a document contained within a different wiki (An InterWiki link). Some examples;
CamelCase words are wikilinks
This takes you to the front page
FrontPage so does this
http://www.tsmwiki.com/tsmwiki/FrontPage So does that !
For more information, see HelpOnFormatting