Forum:Someone added a hidden category to my wiki.

Someone (or something) called QATestsBot added the following page (and category) to my wiki: http://theland.wikia.com/wiki/Category:Pages_with_broken_file_links

It doesn't seem to have any content, and I don't know what a "hidden category" is. Should I be concerned about this? My inclination is to delete the page, but I wanted to make sure it's not something the Wikia staff is doing for some reason. Teknomage (talk) 13:29, September 22, 2012 (UTC)
 * It's an automated addition a category that will list pages that link to nonexistent images. Hidden categories are categories that are only visible when the user specifically enables it in their preferences. To hide a category, add __HIDDENCAT__ into it. TK-999 (talk) 13:32, September 22, 2012 (UTC)
 * As one of the champions of hidden categories (HCs) on Wikia, I think I should jump in and sing their praises. The default condition for IP and registered users is that hidden categories are unseen.  And most people never take the time to go to the bottom of the "Under the Hood" section of Special:Preferences to enable HCs.  This gives admin an opportunity to create any number of administrative categories, and to hide their generally impenetrable names from the average reader of your site.  For instance, this category name you found is something that the average reader would puzzle over.  "What the heck is a broken file link?", the Wikia-initiate would almost certainly ask. A newbie would certainly wonder what an article with invalid date parameter in template is! Because it's an HC, though, the average reader never encounters it.


 * Similarly, if you have really long category names — like, I dunno, articles containing potentially dated statements from May 2012 — you can keep the category box at the bottom of the page free of the clutter.


 * But, you retain a category name that's usefully precise. You don't have to think, "Yanno, this category title is so obscure that it's gonna seriously confuse people, or so long that it's gonna make the bottom of the page a crowded mess". HCs give you the power to perform maintenance, and most readers won't even be aware that there's a technical problem with the page.


 * Think of hidden categories as a way of sweeping up from underneath the floor.


 * At w:c:tardis, we've found they're also of tremendous benefit in running the Achievements game. Since Achievement editing tracks are entirely defined by categories, you can — indeed, you almost must — get creative with your categories in order to make the game more fun.  Sometimes, this will mean completely making up a new category that only has relevance to the game.  Maybe you'll combine two related categories — say, story editors and script editors or Torchwood guest actors and Doctor Who guest actors — that you need to otherwise keep separate.


 * Or you might want to keep the category hidden because it doesn't fit in with general best practices on your wiki. Imagine that you have a category structure whereby you keep things nice and clean.  In this structure, you've decided that pages should be categorised as specifically as possible. So, generally speaking, you'd have a structure like this:


 * Category:Food
 * Category:Fruit
 * Category:Tree fruit
 * Page:Apple


 * In normal circumstances, you wouldn't put Apple directly under Fruit or Food. Instead you'd keep it under the most specific category possible — Tree fruit. But for the running of your achievements game, you need to do an editing track for all Food. So you temporarily assign Category:Food to all pages that are under the meta-category of Food, but you hide Category:Food.  That way, most people won't know that you've broken one of the general rules of categorisation on your wiki.


 * Hidden categories are like the water level of a pond. They make the duck look like she's gliding across the pond, when in fact she's kicking away furiously. 15:57: Sat 22 Sep 2012


 * Why's it wrong to categorize a tree fruit as food? There might be other kinds of ways to group food besides tree fruit, for example. Like "red fruit" or "food high in vitamin C". Like a lot of character pages will always be under characters in spite of also having additional subcategories. +Yc 08:54, September 28, 2012 (UTC)


 * To answer the specific concerns of the original poster; I've noticed this on all wikis on which I'm an admin and thus keep an eye on RecentChanges. In some cases it's been added by WikiaBot, in others by an IP address; sometimes with an explanation that it's to hide this maintenance category, sometimes without explanation.  It's an automated process (the bot has been working through the wikis, adding this to every one) and it's a harmless and useful one. -- RobertATfm (talk) 13:18, September 29, 2012 (UTC)