People who work with Wikipedia quickly run into the interlanguage links – links to other versions of the same article. Inside Wikipedia lingo they are also frequently called “interwiki links”, although actually it’s not quite right: Interwiki links is a much wider concept.
Wikis existed long before Wikipedia was the most popular wiki of them all. They were a strange idea – websites that anyone could edit. They tried various ways of creating an inter-wiki community, in which different wiki communities would exchange ideas and reuse content and skills. Various schemes to do that were proposed, but none of them ever caught on – the old-days wikis were respectable, but small, and the web was too large and free-form.
And then Wikipedia came. Wikipedia started as a yet another wiki, so it tried to blend in the wiki community. At some point it got interwiki links – easy ways to link to other websites. It is easy to link to another page inside the same wiki by adding square brackets, and it is only slightly harder to link to another wiki: Instead of writing a whole URL with http and all that, you would just write a short prefix and a name of a page, and that’s it.
But to which wikis it is possible to link? Thanks to the popularity of Wikipedia, MediaWiki and other wiki engines, there are thousands of them now, and you don’t have prefixes for all of them. The prefixes for Wikimedia projects were managed in the internals of the database by the small group of developers. The list was exported to the Wikimedia Interwiki map. And actually… it wasn’t used that much. The old dream of having a network of wikis which are not just Wikipedia hasn’t come true yet. But this may change now, because recently the process became more open and user-friendly: The Interwiki extension was installed on Wikimedia wikis.
This extension allows displaying all the available interwiki prefixes in a dedicated table. It also allows users with appropriate preferences to edit them. Take a look at the Interwiki table for the English Wikipedia and you’ll see all the prefixes. Many of them are language codes – these are the interlanguage links. But there are many others: wiki communities of city residents, scientists, programmers, librarians, enthusiasts of countries etc. If you try the URLs in the list, you’ll see that some target sites are sadly dead, so they should probably be removed from the list. But others can be quite promising – for example Appropedia, a knowledge base of collaborative solutions in sustainability, appropriate technology and poverty reduction. That’s a very positive thing, not just because sustainability is a nice thing, but because it’s great to have many specialized information sources and not just one huge Wikipedia.
Now Wikimedia wiki communities can add their own interwiki prefixes to link to other websites that may interest them. An example off the top of my head is that the Slovak Wikipedia community would add a prefix for easy linking to a site with information about Slovak culture. Of course, the language and the topic can be just about anything.
This feature, just like all other MediaWiki extensions is translatable to all languages in translatewiki.net. For example, here’s the translation of the Interwiki extension to Hebrew. The translation of the Interwiki extension to the Slovak language, which I mentioned earlier, is not complete yet and should be completed. If you are curious in translating the extension or any other component of MediaWiki into your language, open an account at that website and just start translating.