This template is for use on "maintenance" category pages, ie. those which are used by administrators and pages which use special features (such as the DPL mechanism for dynamic page listings) and are not of interest to the typical user.
Use this template on a category page to hide it from being listed on pages that use the category. Category pages on which this template appears will be categorized in Category:Hidden categories. -- Chucktalk Giffen♫ 01:43, 8 April 2008 (PDT)