From SCDimensions

Category:Help contains help pages that describe how to use MediaWiki. Only pages in "Help:" namespace should be in this category. Note that all pages in the Help: namespace are released into the public domain so that they can be easily imported into any MediaWiki instance regardless of the specific wiki's own license. See Project:PD Help if you want to help us.

All English-language public-domain help pages should be categorized into Category:Help (using [[Category:Help]]), for documentation of the MediaWiki core interface, or Category:Extension help (using [[Category:Extension help]]) for extension documentation. Additional categories for further sorting is also helpful. This is needed because of later half-automated creation of the PD Help package from this category.

The front page is Help:Contents