Commons talk:Categories/Archive 3

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{{MetaCat}} template problem

Before anyone starts to complain: I have changed the link in the template to point to Commons:Categories#Categorization_tips. Non-English versions might need updating though (I don't know whether they exist). This is perhaps just an interim measure, until we can get "official" working meta-cat guidelines.

The rationale is thus: Previously, the link led to Commons:Naming_categories#Categories_by_CRITERION, but if you see the Talk page there and browse the CfD archive, you will note that the proposal has been roundly rejected and torn to pieces for its sheer unworkability. Users must not be led to believe that this "Category: a of b in x of y by z" nonsense is actual policy.

(I note that aggressive unilaterality and a certain amount of "sneakiness" are problems Commons cannot well suppress. en: for example does a much better job. Possibly, a major reason is that en: leaves more leeway to individual sub-projects, while the aim on Commons seems to be a one-size-fits-all categorization scheme. Also, discussions on en: are usually vigorous enough to resolve every problem, whereas on Commons problems are only discussed when they are close to the breaking point or already beyond.) Dysmorodrepanis (talk) 15:21, 11 February 2011 (UTC)

I reverted the meta cat change for the simple reason that the by criterion categories part has never been contested and that I had already to reject many hundreds of meta categories attempts based on that definition. Pointing it to tips does not help as it contains no meta cat definition. For some reason, people believe that if they define a cat as a metacat, it will remain clean and there will never arrive images in it. --Foroa (talk) 17:37, 11 February 2011 (UTC)
Nooooo! See the discussion page there and a lot of CfD items of 2010 - the MetaCat scheme the template links to was never accepted, and by the way the discussion ran I'd rather say it was crushed, torn to shreds, burned and stomped into the ground (there were so many objections that "disputed" is too mild a word). In effect, this way people will click on "Metacat" in the tempate, expecting an explanation, and arrive at a detailed category scheme that was, however, never accepted. Users will skip over the "Naming categories" pageheader: "References or links to this page should not describe it as "policy"."
So basically, to link to "Naming categories" is at least questionable, if not a major violation of policy (a link in such a prominent place, it might be argued, implicitly suggests the link target is official policy). Dysmorodrepanis (talk) 16:42, 14 February 2011 (UTC)
The category by topic part has never been contested. So the best solution is to isolate it in a separate article. --Foroa (talk) 11:42, 17 February 2011 (UTC)
The entire proposed meta-category scheme has been rejected, and for good reason. Read the discussion please, it is unworkable.
Please be also aware of the header at Commons:Naming_categories. It uneqivocally states that this is NOT policy AND MUST NOT BE MADE LOOK OFFICIAL PERIOD. There is no mincing of words allowed here. You yourself pointed out the unofficialness of the entire scheme back in 2009. And I cannot see how the points you brought up back then have been resolved. Hence, no, we cannot link to "Naming categories" in this way. Dysmorodrepanis (talk) 10:42, 16 April 2011 (UTC)

South Sudan subcategories?

I would suggest to create Category:Maps of South Sudan – to include all maps of South Sudan without northern Sudan as well as maps that highlight the whole of South Sudan within Sudan, whereby the latter would also remain within Category:Maps of Sudan –, of course as a subcategory of Maps of Sudan until independence of South Sudan is formally declared. In the same manner, I would like to create Category:Cities and villages in South Sudan as a subcategory of Category:Cities and villages in Sudan. Does anyone object to me doing this? Béka (talk) 13:25, 26 February 2011 (UTC)

Check out Category:Korea. Sudan could probably be handled in a similar way. That "Northern Sudan" retains the old name is a crucial difference; perhaps someone has a workaround. Dysmorodrepanis (talk) 10:54, 16 April 2011 (UTC)

Which way to go on a currently hidden category?


Category:PD Seattle Neighborhood Atlas, a subcategory of Category:Maps of Seattle, is currently a hidden category. I can go either way on whether that category is hidden or visible; personally, I'd just make it visible, but if people think not, no big deal. However, this crosses over in a weird way with the rule about not putting the same file in both a category and its supercategory: if Category:PD Seattle Neighborhood Atlas remains a hidden category, then these maps are not Category:Maps of Seattle or any of its non-hidden subcategories. So, should we make Category:PD Seattle Neighborhood Atlas non-hidden, or should we be attaching some other non-hidden category that reveals that these are maps of Seattle (mainly of Seattle neighborhoods)? - Jmabel ! talk 04:04, 24 April 2011 (UTC)

I can't for the life of me figure out why Category:PD Seattle Neighborhood Atlas is a hidden category in the first place. --Skeezix1000 (talk) 17:33, 27 April 2011 (UTC)
Same here --Jarekt (talk) 20:41, 27 April 2011 (UTC)

OK, then I'll just unhide it, and not worry that some of the items in there (those I uploaded recently) will be redundantly in Category:Maps of Seattle. If anyone can use a bot to clean that up, great. - Jmabel ! talk 22:54, 27 April 2011 (UTC)

Categorising images by year of creation

I have noticed that some images are categorised by the year the image was made. For example there are images in Category:2007 in New Zealand even though there is nothing in the image that would be related to the year of the category. That is to say the image could be taken in any year and would essentially be the same. I don't think this is a worthwhile way of categorising images. It clutters up categories. Alan Liefting (talk) 05:50, 8 May 2011 (UTC)

It's pretty subjective as to whether the images pertain to 2007 or not. Personally, I don't believe that there are many images that are "timeless" - the condition of a building, the contents of a streetscape, the farm field before it was redeveloped, the photographic methods -- these are all inherently tied to the time the image was taken. Nobody ever says categories like Category:1927 in New Zealand or Category:1957 in New Zealand are worthless, because we have enough perspective to appreciate that the images in those categories speak to the year in which they were taken - we shouldn't be blind to those same qualities in images that are (at the moment) more contemporary. In any event, I am at a loss to understand how such categories clutter up anything. --Skeezix1000 (talk) 14:56, 8 May 2011 (UTC)
@Alan Liefting, see in this respect also the discussions which took place about a year ago. I am not surprised to see who made this Category:2007 in New Zealand. Making these cats seems to be much easier than deleting them. I tried, but I failed. I would absolutely welcome a more reasonable policy in this matter though. The example I took last year (Category:1994 in Honduras) was not at all an example of streetscapes or photographic methods, but a category created due to the amazing coincidence that I happened to travel Honduras in 1994, and not in 1995 or in 1993, and decided to throw my old photocamera away after, and not before, that trip. May be the Tela-picture would be interesting if you want to compare building-conditions during the years. But I suppose the Category:Tela serves much better for that purpose. Hettie (talk) 20:26, 8 May 2011 (UTC)


Hello. I would like to ask about the Category:Ukrainophobia. Is it really necessary? It allows categorization of every single person labeled as "Anti-Ukrainian". Moreover, equivalent category doesn't exist even at EN Wiki. - Darwinek (talk) 08:03, 11 May 2011 (UTC)

That category doesn't look encyclopaedic... --Arcibel (talk) 22:45, 11 May 2011 (UTC)
Is there any place on Commons, where I could nominate it for deletion? - Darwinek (talk) 12:30, 16 May 2011 (UTC)
The category has 4 interwiki links to articles. I think it is as valid as antisemitism or other prejudices. --Jarekt (talk) 14:34, 16 May 2011 (UTC)
Bring it to Commons:Categories for discussion. Ww2censor (talk) 15:29, 16 May 2011 (UTC)
Can you useful add the link overleaf (this site)? --Perhelion (talk) 22:31, 29 May 2011 (UTC)

Archives not showing

there is a very nice link to the concept of archiving a talk page, but where are the archive links? TCO (talk) 17:51, 4 June 2011 (UTC)

Fixed. --  Docu  at 11:00, 6 June 2011 (UTC)

Commons:Category structure

I split out all the category structure stuff from this mess of a page to Commons:Category structure. This was reverted apparently on the basis of being "undiscussed". Well, discuss away. See also Commons:Village_pump#Commons:Category_structure. Rd232 (talk) 17:08, 10 June 2011 (UTC)

The proposal seems to have remained unsupported. I redirected Commons:Category structure back here. Otherwise we will just have another page about categories that isn't even called "Categories". The tools section seems easier to split out. --  Docu  at 05:37, 19 June 2011 (UTC)
Further discussion at Commons:Village_pump/Proposals#Split_Commons:Categories, if anyone's interested. Rd232 (talk) 12:46, 20 July 2011 (UTC)
I think it's easier to discuss it here, otherwise we might loose the valuable comments on this as it happened the first time you brought this up.
Is there any issue with my proposal? --  Docu  at 01:49, 21 July 2011 (UTC) (edited)
Commented at COM:VPR. Rd232 (talk) 09:44, 21 July 2011 (UTC)
Actually, I like your suggestion to split out tools and how-to sections.
It's a bit regrettable that you choose to ignore the previous discussion of your proposal. Apparently you are not used to work with feed back. --  Docu  at 06:23, 23 July 2011 (UTC)
By "previous discussion" do you mean your passing remark after reverting my initial page split? Rd232 (talk) 08:20, 23 July 2011 (UTC)
Seems odd that you forgot about the previous discussion.
Is there any specific issue you are trying to solve? Maybe you could just start a Commons:Template categorization outline. This might help you with your work at Commons. --  Docu  at 08:33, 23 July 2011 (UTC)
Oh, you meant your enormously helpful contributions at Commons:Village_pump/Archive/2011/06#Commons:Category_structure_amendment? I rebooted it at Commons:Village_pump/Archive/2011/06#Commons:Category_structure_creation. Neither thread got any substantive input on the proposal. Yes, I did try and forget that, and frankly, it's bizarre you want to bring to attention to your behaviour in that episode. Rd232 (talk) 11:38, 23 July 2011 (UTC)

Art by location vs. by origin

What does one do to somehow tie an image like this to the fact that the sculpture is of Thai origin? I can't really use Category:Sculptures in Thailand, because it was physically located in Seattle, Washington. But surely there ought to be some way to tie the art to its nation of origin. - Jmabel ! talk 04:36, 27 July 2011 (UTC)

Easy: Category:Art of Thailand abroad + Category:Sculptures in Seattle. Dysmorodrepanis (talk) 12:29, 23 September 2011 (UTC)

Category order

Hi. Are there any guidelines or advice concerning the order of the categories or is it all free style? For example, in Category:Schrotthorn which is the 'best' order of the three cats? Gun Powder Ma (talk) 19:59, 7 November 2011 (UTC)

Pretty much freeform. If there is theoretically a standard, not enough people are aware of it for it to be much use. - Jmabel ! talk 20:08, 7 November 2011 (UTC)
Thanks. Given the lack of response from other users, it seems that there is indeed no recommended order of any kind. Gun Powder Ma (talk) 10:45, 9 November 2011 (UTC)


How would you categorize the river Category:Adige which runs through the Italian regions of Trentino-South Tyrol and Veneto?

  1. Category:Rivers of Trentino-South Tyrol and Category:Rivers of Veneto
  2. Category:Rivers of Trentino, Category:Rivers of South Tyrol and Category:Rivers of Veneto

Gun Powder Ma (talk) 09:13, 11 November 2011 (UTC)

Sortkey promotion of location-specific subcats

Today I ran across some cases in which location-specific subcategories were being "promoted" via sortkeys to the top of the subcats list in non-location-related parent categories. In particular, for example, Category:Concepts in the United Kingdom was categorized using [[Category:Concepts| United Kingdom]] (note the space) so that it appeared at the top of the list of subcats in Category:Concepts. Now, I don't see any good reason to do this sort of thing, so I started removing the space at the beginning of such sortkeys (so Category:Concepts in the United Kingdom ends up sorting under "U" in Category:Concepts). I assume the way I'm doing it would be the consensus view here, but I have found many more examples where it's done the other way. I'd like an "OK" from someone who's more familiar with category sorting here at Commons before I make any more of these kinds of modifications. Thanks. - dcljr (talk) 23:54, 7 December 2011 (UTC)

Sometimes this space or other symbol is used to create multiple sorted lists. For example Category:Vehicles by country uses main sort list for categories related to "Vehicles" in each country, but also uses space in front of the sortkey to create second sorted list for different types of vehicles "by country". If you are removing any such spaces please make sure you are not mixing apples and oranges. In case of Category:Concepts in the United Kingdom and Category:Concepts all other types of subcategories in Category:Concepts are for different concepts. Such category would usually have a few [[:Category:Concepts by X| X]], in front of other subcategories. However in this case there was only Category:Concepts in the United Kingdom. I would prefer the previous order. --Jarekt (talk) 02:27, 8 December 2011 (UTC)
Indeed, sort keys are often used to group a number of (often meta) categories according to a certain logic that is different from the main category logic, as to avoid yet another intermediate category. An example in Category:Buildings by country where the top left categories are some sort of "side" categories". See alse discussion on User_talk:Look2See1#Odd_sorting_-_interior_cats_vs._subcats. --Foroa (talk) 06:40, 8 December 2011 (UTC)

Language mix in category naming

A relevant conversation: Commons:Village pump#Language mix in category naming.--Codrin.B (talk) 20:42, 8 February 2012 (UTC)

Subcategory loop

Ought subcategories form a closed loop? An editor who generally does excellent categorizations of photos has disagreed with me on this point, in Category talk:Home Life Insurance Company Building. Jim.henderson (talk) 16:47, 17 February 2012 (UTC)

Category and template

Hi. What is the difference between Category and template ? For example : templates Created with and Category:Images by software used or Category:Diagrams created with. Regards --Adam majewski (talk) 10:46, 10 March 2012 (UTC)

Take a look at Commons:Templates. Allan Aguilar (talk)   19:46, 10 March 2012 (UTC)

Overcat problem with Template:ComuneItaly

The template is designed to create mass overcategorization. Because it puts the category of any italian village in some parent categories of the most specific one. I've been in a discussion with one of the main authors of the template but he disagrees. Can someone independent have a look on the matter and give advise? Thanks --MB-one (talk) 17:05, 30 July 2012 (UTC)

Dates in category names

Please see Commons:Village_pump#Format_of_dates_in_category_names. Rd232 (talk) 16:21, 9 January 2013 (UTC)

Creating a new category

Crosslink / info: There is a question about here: Com:VP#Commons:_Categories -- ΠЄΡΉΛΙΟ 15:28, 15 January 2013 (UTC)

Redundant categories

I encountered a couple of redundant categories: Category:Dorfgemeinschaftshaus, Category:Dorfgemeinschaftshäuser. Where is the place to discuss this redundancy? --dealerofsalvation 07:07, 4 March 2013 (UTC)

Hi! I have just moved the content from the one to the other category. Category:Dorfgemeinschaftshäuser is preferred because of its plural form. Thank you for your support. Normally you can post such things on COM:VP. Best rRgards, High Contrast (talk) 17:05, 4 March 2013 (UTC)
Thanks for doing all the work ;) I just fixed the Commons link in dewiki. --dealerofsalvation 05:14, 5 March 2013 (UTC)

Designs by designer

I was thinking that we should have categories something like "Designs by designer"; meaning for example all images that feature designs by fashion designer Manish Malhotra can be included in it. I think the category is a valid one. We have Category:Paintings by painter and Category:Buildings by architect and this will be on similar lines. But i am not sure of what nomenclature should be followed here. Also i am surprised that no such category already exists (per my search). What should the name be? §§Dharmadhyaksha§§ {T/C} 07:04, 3 April 2013 (UTC)

How to find the appropriate category

I uploaded a file, I know exactly in what category it has to be placed, I'm sure this category exists, but .... it seems almost impossible to find this category. All the help pages, instruction pages, etc, etc, are of no help at all. Nijdam (talk) 09:51, 7 April 2013 (UTC)

Did you find it? I looked through your uploads, and all the items already appeared to have corresponding categories. If a specific search for a category doesn't return anything useful, you can start from the top at Category:Topics and try to specify down from there. If you have exhausted all your options and knowledge, you have good grounds for creating a new category. If it's not the correct one, someone with better knowledge can rectify it, and no harm has been done. ~ Nelg (talk) 16:44, 23 April 2013 (UTC)
You can use category of wikipedia article about the same item. HTH --Adam majewski (talk) 16:50, 24 April 2013 (UTC)

"Way of Life"

Some additional input at Commons:Categories for discussion/2012/04/Category:19th-century way of life would be welcome. Thanks. --Skeezix1000 (talk) 13:19, 8 May 2013 (UTC)

View all from category

Hi...I want to list all Pictures in Category:Paintings plus all pictures in one of its sudirectories in some kind of gallery. Is this possible? Generator (talk) 08:27, 29 August 2013 (UTC)

The Mediawiki software doesn't enable it yet. Support this bug report to request for this enhancement. For now, the script FastCCI displays 3 clicable icons at every category page, which display images from the category and its subcategories. For now, this function displays only images filtered by the selected of the 3 predefined filters only (tagged quality images). It was requested to make the script more universal to display unfiletered content or contend by selectable filter/criterium. --ŠJů (talk) 10:19, 2 February 2014 (UTC)

Legitimate cases of over-categorization

Belongs in cat:Dih4 cycle graphs because the top vertex shows a Dih4 cycle graph, but it would be wrong to remove its parent cat:Dih4 because this image is no cycle graph.

I sometimes stumble upon images that illustrate foo in general, and thus should be in cat:foo - but also show some detail of foo, so that they should be in cat:foo detail as well. (See image on the right.) Technically this is COM:OVERCAT, but I think it is the right thing to do. Opinions? Maybe the guideline COM:OVERCAT should define cases where this is legitimate. mate2code 14:55, 28 February 2014 (UTC)

My opinion on this is rather strict. If this image shows two different aspects of foo it should be in two different subcategories of foo but not in Cat:foo and Subcat:foo. In other words there is no „shows topic in general“, images or media always show specific aspects. --MB-one (talk) 09:01, 14 May 2014 (UTC)
Mate, this does occasionally come up. COM:OVERCAT does state it is a "general rule" because occasionally there are images that arbuably belong in a parent and sub cat. Having said that, I am not in favour of trying to define cases where this would be permitted. It's already hard enough to enforce COM:OVERCAT in balck-and-white cases without additional vague text about "legitimate" violations (which people will inevitably use to drive a truck through COM:OVERCAT). Best left alone. --Skeezix1000 (talk) 15:05, 14 May 2014 (UTC)

Branching and crossing of categorization threads

I've removed this section from COM:OVERCAT (I've copied it below). If there was discussion with a consensus to change OVERCAT to add this exception, then my apologies and please let me know. Otherwise, it is problematic. First, it's very difficult to understand. I'm a lawyer, I interpret dense legalese every day, yet I do not find this particularly clear. There must be a better way to describe this than referring to "a multifactorial net with multihierarchic traits". Second, I am not sure that I necessarily agree. Just to use the same example of the regional administrative office. It isn't a given that the file should be categorized directly in the subcat for the street as well as in the main parent category for the region. I would consider that COM:OVERCAT. The better solution would be to create a subcategory for regional government buildings or for the regional government. Anyway, hopefully we can sort this out. --Skeezix1000 (talk) 18:38, 7 July 2014 (UTC)

"Note that Commons category structure (as well as Wikipedia categorization) is not a simple hierarchy (like biological taxonomy) but rather a multifactorial net with multihierarchic traits. That's why one subject can be categorized into any category by one factor and into its parent category by another factor and such categorization should be not considered as overcategorization.

  • Example: a category of the Regional Office is categorized to the category of the street where the office bulding is. As regards location, the building should be not categorized directly into the category of the city or the region. However, by attribution it should be categorized into the category of the region because the office is an administrative body of the region and the building is owned by the self-governed region. Such categorization is not overcategorization even though the second category is a parent category of the first category.
  • Similarly, a category of a village which is part of a municipality can be categorized under the neighbouring village by cadastral division (because it fall under its cadastral area) and simultaneously directly to the category of the municipality (because both villages are co-equal municipal parts administratively).

Exceptionally, different categorization threads can even meet each other in the opposite direction (category A is subcategory of B by one factor and simultaneously category B is subcategory of A by another factor) and can create a quasi-cycle. However, such a solution is not preferred and should be avoided if possible."

--Skeezix1000 (talk) 18:38, 7 July 2014 (UTC)

@Skeezix1000 The fact itself that the categorization on wiki projects is not a simple hierarchy but is multifactorial (use more types of relations, not only hyponymy, not only meronymy) is established and consensual enough.

However, some users don't comprehend consequences of this basal and consensual fact. We should expect that not all uploaders (users, editors) are capable to understand all consequences of this system, though they can be capable to consume their benefits. The fact that "one subject can be categorized into any category by one factor and into its parent category by another factor and such categorization should be not considered as overcategorization" follows from the consensual categorization principles - removing of this warning from the policy can cause that people which are not capable to understand the categorization system will disrupt and destroy it under their faulty sense that they rectify "over-categorization".

Surely, as you propose, such a seeming "over-categorization" can and should be effectively reduced or avoided by such a "explaining middlecategory" which indicates - in our example - what is the reason why the building is categorized under the category of the region (because the categorization tag itself does not enable to mark and distinguish a type of categorization relation). However, we should emphasize that the fact that the file is categorized into a subcategory by one categorization criterion doesn't imply that it should be removed automatically and thoughtlessly from the parent category - it can belong to it from a different categorization reason/criterion (if the parelel subcategorization structure by such a criterion is not created yet). Wee should and need to underline that true over-categorization can be judged and stated only within one categorization criterion and type of relation.

I agree with you, such a "seeming over-categorization" should be also avoided. However, it should be treated in a different way than the "true over-categorization" and distinguished from it. The true over-categorization should be treated by simply removing from the parent category in most cases (or can be deputized by a paralel flat category - by name, by ID etc.). The "seeming over-categorization" can be treated by explaining auxiliary mezzocategories, never by removing from the parent category. However, in some cases, too many categorization levels are worse problem than the "seeming over-categorization" of one or two files. --ŠJů (talk) 19:44, 3 September 2014 (UTC)

Flat categories

I propose to add a section about "flat categories" into the section about over-categorization: --ŠJů (talk) 18:47, 3 September 2014 (UTC)

Flat categories

Some types of categories are meant as so-called flat categories. Such categories are not intended to be organized and to group their content into their subcategories. Most of them are hidden "technical" or maintenance categories which group files tagged with an appropriate tagging template. However, some item categories, especially categories "by name" or "by ID number" etc. (as People by name) have also less or more such a flat character. Such flat categories can be used by maintenance bots etc. Try to discuss before you create subcategories in such cases.

Question "Templates for categories"

Help and translations

It's quite a shame, but it seems we don't yet have a translatable help page on categories; one is desired, see [1]. Can a translation admin make this page translatable and/or split part of it to Help:Categories and make that translatable? --Nemo 11:06, 22 April 2015 (UTC)

The help link will be customisable by entering a new target title in MediaWiki:Namespace-14-helppage once MediaWiki is updated, but we still don't have a translatable help page here. :/ --Nemo 10:52, 15 May 2015 (UTC)
Steinsplitter, see above and mw:Manual:Page customizations. --Nemo 22:09, 26 May 2015 (UTC)

Requirement: Creating a new category (recommendation)

Cross talk link → Commons:Village pump #Requirement: Creating a new category (recommendation) User: Perhelion (Commons: = crap?)  10:24, 2 June 2015 (UTC)

Commons:Naming categories

Cross talk link → Commons:Village pump #Commons:Naming categories User: Perhelion (Commons: = crap?)  14:25, 15 July 2015 (UTC)

Over categorisation of files containing small glimpses of unrelated items

South Korea Supreme Court, also depicting cars in small detail

Today I had a discussion with another user about a form of over categorisation that I believe to be a problem at Wikimedia Commons. I think it is appropriate to bring it up here for the involvement of other editors. For example, this file of the South Korea Supreme Court illustrates its intended subject very well. However, I do not believe it to be very useful at illustrating Hyundai Sonata automobiles which the image is also categorised in because it contains a small glimpse of the said vehicle. By the same token, one could also add categories for the deciduous trees, the sky, power lines, the road, and foot path/side walk. These also make up a small/minority part of the image. However, none of these items contained within the image would be particularly useful for someone searching for a photo of a road or a tree.

Considering that most images of locations in built-up areas taken near a road will contain vehicles as incidental subject matters, the systematic categorisation of these vehicles cause massive over-categorisation problems.

To me, if it bothers a user so much to have such items as "unidentified" so to speak (because there is not category to specify exactly what the minority items are), then Commons would in my view be better served by using annotations on the image itself or by placing a note in the description. Clogging up categories with junk seems quite counterproductive.

Would there be support for the inclusion of a usefulness/relevance clause into COM:Categories? OSX (talkcontributions) 05:51, 17 July 2015 (UTC)

I agree on the principle, but I'm concerned about contributing to instruction creep. The Commons:Categories#Categorization tips section already mentions that categories should be set based on the main subject and noteworthy features. LX (talk, contribs) 06:07, 17 July 2015 (UTC)
I also agree and have seen and cleaned up this problem in the past. (For example Category:Overhead lines in Germany had lots of random images of trains and railway lines which happened to have an overhead line. Duh.) But I also think that the instruction about "main subjects" and "noteworthy features" is sufficient. --Sebari (talk) 10:48, 17 July 2015 (UTC)

interwiki linking

Can somebody confirm that interwiki linking should now be done via Wikidata and maybe also change the page to reflect that (see Commons:Categories#Creating a new category)?--Ndevor (talk) 09:47, 10 September 2015 (UTC)

I think the current situation still is that you can use Wikidata for interwiki linking, but without a broad consensus that you should do it. Some actively remove the traditional interwiki links in favor of the Wikidata function while others keep on adding them. IMHO, anyone wanting to achieve more uniformity would have to draft some clear instructions and discuss the issue at the proposal section of village pump. But considering the technical and practical shortcomings of Wikidata, I´m not sure if there´s a majority for any change. --Rudolph Buch (talk) 15:58, 10 September 2015 (UTC)

One-image categories?

I find nothing on whether or not we should create a category for only one single image. Has it been discussed and is there policy on that? --SergeWoodzing (talk) 09:18, 19 March 2016 (UTC)

I'd say it depends on the nature of the category.
Categories for notable people often make sense even for a single file. One reason for this is to allow categorisation under Category:People by name, which is only supposed contain other categories. Another is to allow separation between categories related to the person (e.g. year of birth, nationality, profession) from what's seen in a particular image (e.g. women with glasses, men with beards). If you apply those directly to a file instead of creating a category for the person, someone creating the category later on has to (1) have the initiative to search for other files to put in the newly created category (2) actually find the file (3) separate the categories pertaining to the person from the categories pertaining to the file itself (4) remove the former from the file (5) add them to the person category and (6) place the file in the category.
In some cases, even categories with zero files make sense. When I cleaned up Category:Districts of Stockholm, I created categories for all the districts, even if there were no files to place in them at the time. The category tree would not have been complete without them, and it was obvious that it was only a matter of time before they would be populated. Category:Lunda, which was empty for some time, now has a couple of files and even a subcategory. Category:Hansta is still waiting for its first file. Once someone uploads a relevant file, that greatly increases the odds that it will be correctly categorised.
Categories exist to help find existing files and to categorise new files. Overly specific categories that are unlikely to ever have more than one file are probably not useful for those purposes. LX (talk, contribs) 10:58, 19 March 2016 (UTC)
I agree with User:LX. Also keep in mind that categories on Commons are not comparable with categories on the Wikipedias. Most categories of current subjects will fill up with time when more photos are taken, since the number of possible photos of a subject is basically unlimited. At the Wikipedias, on the other hand, a certain subject only has a limited amount of possible encyclopedic relevant sub-topics. --Sebari (talk) 13:56, 19 March 2016 (UTC)
Thank you both! --SergeWoodzing (talk) 08:34, 20 March 2016 (UTC)

Spinning off new categories

At what stage should a new category be spun off? Consider the following example. Suppose that I find the category "Public libraries in the United States" has become too large. That category could then be broken down into 51 sub-categories – one for each state (counting Washington DC as a state). Since the United States and Luxembourg are both sovereign independent states, should I also break the category "Public libraries in Luxembourg" down into a number of sub-categories – one for each administrative sub-division of Luxembourg. I think that the answer is "No", but why not? The real answer, I believe, lies in the size of the resultant categories.

May I suggest that a as a guideline well-defined category that contains fewer than 10 images should not be broken up, one that contain 100 images should be broken up while discretion should be used for a category with between 10 and 100 images. Martinvl (talk) 07:14, 31 March 2016 (UTC)

The concept is reasonable, but putting hard numbers to it is a mistake as that may be interpreted as "must do" not "consider doing". It depends on the situation - sometimes a large number in a single category is OK, but sometimes a much lower number is not tolerable.
Also bear in mind these concepts are not always straightforward subdivisions of one large concept. For instance if there are just 5 images in "Libraries in Luxembourg" there still might be a real need for "Libraries in Luxembourg City", because "Buildings in Luxembourg City" has hundreds of files.--Nilfanion (talk) 10:06, 31 March 2016 (UTC)
There is no hard and fast guidelines of when to break down categories. Sometimes it is useful to create a category with only one file in it. Also, just because you subdivide the libraries in the US does not mean you have to do the same in other countries. Also remember that most categories will get more photos with time, so they will need to be split up eventually anyways. --Sebari (talk) 22:35, 31 March 2016 (UTC)


Images often get categorized by date for no good reason, spamming date categories with irrelevant images. I propose that the text under categorization tips is supplemented. To the text that reads

"when?: when did the depicted events happen, or when was the image created? When was the image taken? This is especially important for historical images. An example would be Category:Warsaw in September 1939, Category:April 2010 in Northern Ireland"

could be added something like:

"Note, however, that categorizing by date is not appropriate for most images. A date-category should contain images that are typical for that time and place. Date-categories are not useful if they contain random events, and they easily become crowded if we use them often. We should ask ourselves what images somebody may expect if they look into a category." --Jonund (talk) 17:28, 13 May 2016 (UTC)

I am not a friend of date categories and hope that with the advent of Wikidata-like structured data Commons (in work), we can get rid of them. (In a few years.) That said, currently date categories serve two separate purposes: dating specific events and showing how something looked like in a general era. Personally, I like the current wording for that reason and am   Oppose to changing it. --Sebari (talk) 19:47, 13 May 2016 (UTC)
That's exactly what these categories should be used for. The problem is that they are often cluttered with irrelevant images. A flower, a person, a logo, a bird are not interesting when you search by date. And a lot of motives may or may not be interesting. A building should be categorized according to date of construction, but usually they are categorized according to when the image was taken, and they look the same over long periods. A street view is often relevant, but if you have a lot of street views it would be proper with a selection. A rock concert is relevant if it is a well-known band, etc. Date-categories are often meaningful only when they describe a specific place or thing. --Jonund (talk) 08:46, 14 May 2016 (UTC)
In practice, the date categories do get flooded with photographs taken on that date. That is useful meta-data to record, and date categories are the only real way we have of doing so right now. If a high-level date category is swamped with photographs taken on that date - just split out the photographs - like how Category:April 2010 photographs is separated from Category:April 2010.
With regards to the examples you mention, the date can be somewhat significant to all those things. Its useful to know a picture of a flower was taken in April, its useful to know a portrait of a person was taken in 2009 etc. If your starting point is the date, you won't care for those files. But if your starting point is the subject, you may find the date useful to narrow down your search.--Nilfanion (talk) 09:03, 14 May 2016 (UTC)
I think it's better to have the date in the description field. In some cases (for instance large categories), subcategories by date are proper for portraits.--Jonund (talk) 18:00, 14 May 2016 (UTC)
The advantage of including the date as a category is it allows searching. If everything in Category:Albert Einstein is in date categories, it is much easier to use existing tools to find any photographs of him in 1945. If its just recorded in the description, its much harder to find things.--Nilfanion (talk) 12:31, 15 May 2016 (UTC)
How often does somebody need an image from a specific year? Most categories are small enough to find the right image easily, and the thumbnails usually give a hint of the approximate year. Large categories, however, may be fit for subcategories by date. (Besides, it's difficult to search by multiple categories.) I'm not advocating a prohibition of date-categories, only discouraging unnecessary and excessive use. --Jonund (talk) 16:04, 15 May 2016 (UTC)
Date categories can be very useful for intersections, such as those produced with catscan. As you say, when categories get large its natural to create sub-categories for <subject> in <date>, but that doesn't make it worthless to include date information when those subcats are not needed. Sure its not particularly high value (I don't add them to my own uploads), but its not incorrect to do so. Its probable that if you went around removing date categories en masse from things you don't see it as valuable on (such as flowers), you would probably get reverted and warned by multiple users. With that in mind I'd   Oppose the change.
If you want to get a broader consensus, please raise this matter somewhere with higher traffic (such as the village pump).--Nilfanion (talk) 17:38, 15 May 2016 (UTC)


Currently, this section starts with an apparent single definition ("Over-categorization is when a file, category or other page is placed in several levels of the same branch in the category tree"). When I give a user a link to this section, they often don't proceed beyond the first paragraph, so they don't understand the concept very well. Typically, many users add categories based on irrelevant items not connected with the main subject, eg people, flora, fauna, objects, etc. I believe that the definition should be expanded to deal with secondary subjects that are irrelevant when they are unlikely to be included in a search by users.PeterWD (talk) 13:33, 11 June 2016 (UTC)

No thanks. People already get confused when you tell them what they're doing is over-categorization, because "two categories couldn't possible be over-categorization". Irrelevant categorization is a completely separate problem. LX (talk, contribs) 14:06, 11 June 2016 (UTC)
The English Wikipedia calls that problem overcategorisation and our COM:OVERCAT WP:SUPERCAT (might explain the confusion, not a reason to change anything here though).    FDMS  4    14:48, 11 June 2016 (UTC)

in the section: Templates for categories there is written


- to provide a table of contents for a large categories with many images and few subcategories

there should be written


- to provide a table of contents for a large category with many images and few subcategories

to avoid (little) confusion. Wilhelm Zimmerling PAR (talk) 15:37, 24 July 2016 (UTC)

Neither version is particularly elegant English. I edited it a bit. LX (talk, contribs) 20:32, 24 July 2016 (UTC)

How can i show the total files in sub categories of a category?

This category contains more than 80 sub categories and also it is a developing one. I want to show the total number of files in those categories. How? I am contributing as a Wikimedian in Residence in TVA. The officials can check easily with that the files number statistics.--Info-farmer (talk) 10:54, 11 September 2016 (UTC)

Use PetScan. --Jklamo (talk) 08:03, 13 September 2016 (UTC)
Very Happy i will inform to others.Bye!--Info-farmer (talk) 08:54, 13 September 2016 (UTC)

Category names with no latin characters

I know that :
Category names should generally be in English. However, there are exceptions such as some proper names, biological taxa and names for which the non-English name is most commonly used in the English language.
But there are some categories with no latin characters. Arabic or chinese characters for example. Here is an example : Category:مدیریت. Are they allowed ? I think that it is a bad idea because it is impossible to understand what they mean. It is also impossible to copy these category names to an european text editor.
I know also that :
Files can be uploaded with names in any language in any script (coded as UTF-8) .
But what about categories ?
I precise that I am not a English language native speaker. I learnt English language which is in fact the universal language. But with arabic or chinese characters it is impossible to know what they gather. --Civa (talk) 22:57, 14 January 2017 (UTC)

@Civa: Such category names should indeed be translated or latinised. The best solution for the specific category is to nominate its members for deletion (they are out of scope) and subsequently get rid of the then-empty category itself as well (which is what I'm about to do now, thanks for bringing this to our attention).    FDMS  4    23:27, 14 January 2017 (UTC)
Thanks for your rapid answer. But perhaps, it should be interesting to add in the Commons policy that the category must be in latin character language (english most often but not always). I already asked deletion of the files in another category : Commons:Deletion requests/Files in Category:سيد صالح --Civa (talk) 23:37, 14 January 2017 (UTC)
I think we're already covered – #Category names states the following:

Latin alphabets are used in original form including diacritics and derived letters, non-Latin alphabets are transcribed to the English Latin script.

   FDMS  4    23:49, 14 January 2017 (UTC)
OK I did not see that. But perhaps it should be interesting to say that at the level of all category names and not only for Particular individual object . Best regards. --Civa (talk) 00:17, 15 January 2017 (UTC)
  Done. This is already common practice for all kinds of categories, the section should now reflect that more clearly.    FDMS  4    00:26, 15 January 2017 (UTC)
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