The term "local help files" refers to any help files that are served from within the same filesystem as the website from which the help request is being made. Local help files can be installed from within a Joomla distribution or an extension package file. In theory, when using local help, it is not necessary to have access to the public internet in order to retrieve help screens. Consequently, local help is useful for those websites where an internet connection is intermittent or unavailable, such as a secure company intranet.
Help files for the core Joomla distribution are served from the /administrator/help/ln-LN/ directory in the local Joomla file structure, where "ln-LN" is the current language code. Installed third-party components will generally serve local help files from a component-specific directory, the default being /administrator/components/com_mycomponent/help/ln-LN/.
In order for local help to work it is necessary to ensure that every key reference in Joomla has a corresponding file in the relevant local help directory. The name of each file must be a valid key reference after localisation by the Joomla language system. For example, the help screen associated with the Article Manager is determined by the tag "JHELP_CONTENT_ARTICLE_MANAGER". If the current language is British English then this tag is looked up in the currently loaded en-GB language files. The language file en-GB.ini contains the following key-value pair:
The help system will then look for a file called either "Content_Article_Manager.html" or "Content_Article_Manager.xml" in the /administrator/help/en-GB directory. Note that because help files may use the ".xml" extension it is possible to write help screens using any XML dialect including DocBook XML; you just need to add an appropriate stylesheet to render the XML elements appropriately.
The administrator help area is populated exclusively by local help files.