!!! Overview
[{$pagename}] is an [HTTP Response] [HTTP Header Field] informs the [User-agent] which [languages] and which [locale] variant provided in the [HTTP Response].

[Language-Tag] is a [Language Code] for a [Language] usually used with [HTTP] and describes more about [{$pagename}]

!! More Information
There might be more information for this subject on one of the following:
[{ReferringPagesPlugin before='*' after='\n' }]