On Wikimedia projects, Babel (anallusion to the Tower of Babel) refers to the user language templates aiding multilingual communication by making it easier to contact someone who speaks a certain language. The idea originated on the Wikimedia Commons and has also been implemented on Meta-Wiki and some of the other Wikipedias to varying extents. To participate, you can add the Babel template to your user page by following the instructions below.
Start off with {{Babel|. The character after the word Babel is the vertical bar (|).
Next add a two letter code for each language you speak or understand, separated by | (another vertical bar). The placeholder xx should be replaced by the Wikipedia code for that language. The general usage of each code level is as follows (note that not all languages have all levels, but you may create the template you are missing); the numbering is approximately analogous to the ILR scale, though this is coincidental:
xx-0 if you cannot understand the language at all. Do not use it for every language that you don't know, but only when there is some reason why you might be expected to know it. For example, one may be of Italian descent, but does not speak the Italian language, or if one is Canadian but does not speak French. Similarly, one may usefully edit a project without speaking the language, such as adding links or images to Japanese Wikipedia without speaking Japanese.
Note: Consensus has been determined at Wikipedia:User categories for discussion that 0-level user categories should not exist on the English Wikipedia. (Non-English-specific wikis may want them for en-0, though.)
xx-1 for basic ability – enough to understand written material or simple questions in this language.
xx-2 for intermediate ability – enough for editing or discussions.
xx-3 for advanced level – though you can write in this language with no problem, some small errors might occur.
xx-4 for 'near-native' level – although it's not your first language from birth, your ability is something like that of a native speaker.
xx (no hyphen or number) for native-born speakers who use a language every day and have a thorough grasp of it, including colloquialisms and idioms.
Note: We do not quibble about the "native-born" part; it's the "including colloquialisms and idioms" part that matters here.
Note: The ordering between this and xx-4 is not particularly meaningful.
xx-5 for professional proficiency – you are able to answer language usage questions that may be asked by native speakers. Note that this template is currently only available for a few languages.
So, for example, {{Babel|en-5|sv|no-4|he-3|lt-2|es-1|an-0}} (see demo on the side) would indicate a professional proficiency of the English language, a native speaker of Swedish with an almost-native knowledge of Norwegian, advanced knowledge of Hebrew, an intermediate knowledge of Lithuanian, a basic knowledge of Spanish, and no knowledge of Aragonese.
These templates add you to the category associated with your level of understanding, and to the overall category for that language.
To find someone who speaks a particular language, see Wikipedians by languages, and follow the links. For the most part, the two and three letter codes are taken from ISO 639, but see this list for a comprehensive guide.
You can help expand this system by creating templates for your language. Categories have already been created for most languages which have editions of Wikipedia containing over a hundred articles; they just need labeling up! It's recommended to copy the English or French versions when expanding the scheme, as most of the languages listed here are incomplete.
Note that many sign languages currently use the same template with language code "sgn", with the exception of American Sign Language users who should use the American Sign Language template. Other sign languages can be specified within the {{User sgn}} template itself. The use of this parameter requires the user to perform an extra step when using the {{Babel-#}} templates, described here.
