Only Wiki Editors and above can validate pages on the wiki. This helps ensure quality.
Pages are validated to ensure quality is not affected on high traffic or highly important pages. Reviewing is handled through the extension "FlaggedRevs" and once a page has been reviewed, it will require revision checks before it can be updated. For this reason, editors—please refrain from approving personal pages and/or discussion/talk pages.
You can read more about reviewing on this page.