Template:Text

_ _ This page, Template:Text, combines the documentation and working code to accomplish a trivial task, and its structure and use are much simpler than the explanation for its desirability. It functions as a MediaWiki-server template with one mandatory argument, which should be a potentially self-referential word or phrase (in English, almost always "This" or "this") in the same language as the page that transcludes or substitutes it. It places that argument, unmodified, on that other page. Its application is in writing a text-heavy template, say A, which places prose on the pages B, C, etc., wherever each transcludes or substitutes A. Its advantage is in saving those reading A from any impression that the word "this" (etc.) refers to A, rather than to some actual B, C, or yet-to-be-coded ?, that transcludes or substitutes A.
_ _ As a trivial example, coding a template {{Non-Tl}} (intended for use on pages that should not be used as templates), with the markup

Do not use this page as a template.

might give the impression of {{Non-Tl}} giving, about itself, the (misleading) direction that "This page should not be used as a template." But coding {{Non-Tl}} with the markup

Do not use {{Text|this}} page as a template.

makes much any such impression much less likely (without the editor who codes {{Non-Tl}} having to learn any template-specific coding techniques, beyond nesting of templates).