en: refers to the English Wikipedia. This is seen in en:Apple Interwiki linking from and within Wikimedia
Within Wikimedia, for the purpose ofen:, de:, etc., from a Wikipedia to another one, from a Wiktionary to another one, from a Wikiquote to another one, from a Wikibooks to another one, from a Wikinews to another one, from a Wikiversity to another one or from a Wikisource to another one.
Example
For example, to link from here to the "surfeit" article on Wiktionary, you would include the wikilink wikt:surfeit surfeit
Surfeit is a human gene cluster that consists of a group of very tightly linked genes on chromosome 9 that do not share sequence similarity. Genes in this cluster are numbered 1 through 6: SURF1, SURF2, SURF3, SURF4
Surfeit locus protein 4 o ...
Prefix codes for linking to Wikimedia sister projects
Unless a language code is added, the following interwiki prefix codes link to the Wikiprojects in English. Note that some links don't work as expected within the same project, e.g., meta:Test on Meta itself would mean m:Meta:Test, a different page. Outside of Wikimedia sister projects, only metawikipedia:Test might work for m:Test. Other current Wikimedia prefixes: betawikiversity:, dbdump:, download:, gerrit:, mail:, mailarchive:, otrs:, OTRSwiki:, outreach:, quality:, rev:, spcom:, sulutil:, svn:, ticket:, tools:, tswiki:, wm2016:, wm2017:, wmania:. See a complete list of current and old but still working prefixes for all Wikimedia wikis at the Special:SiteMatrix. See a complete list of all possible interwiki prefixes at Special:Interwiki. Some of the long forms do not work as expected within the same project; for exampleSpecial versions of Wikipedia
Note that the section above includes two special versions of Wikipedia, nostalgia and nost: testWiki: Linking to international chapters of Wikimedia
Note that these shortcuts ''do not'' link to the versions of Wikipedia (or to other reader-focused, information-delivering projects such as Wiktionary) in languages other than English, but instead link to the localized equivalent oTips for using interproject and interlanguage links
Hiding the visible prefix
To suppress the first, visible prefix in the saved page, use the pipe trick: Add, at the end of the link, like this: test
Test(s), testing, or TEST may refer to:
* Test (assessment), an educational assessment intended to measure the respondents' knowledge or other abilities
Arts and entertainment
* ''Test'' (2013 film), an American film
* ''Test'' (2014 film), ...
en:test, will automatically expand to en:test test
Test(s), testing, or TEST may refer to:
* Test (assessment), an educational assessment intended to measure the respondents' knowledge or other abilities
Arts and entertainment
* ''Test'' (2013 film), an American film
* ''Test'' (2014 film), ...
Doubling prefixes
As demonstrated in the examples below, combinations of certain prefixes are allowed, thus enabling direct page links that are not possible with a single prefix. For example, by combining two prefixes, one can link a word in the English Wikipedia to a term in the German Wiktionary, or link to a category in the Commons. When using language codes, the order of the prefixes does not matter. Remember to put a colon in front of a link starting with a language prefix; however, the colon is optional if the link starts with the project code prefix and then has the language prefix. See the last two examples in the table below. When using the category prefix, the order of the prefixes ''does'' matter. The order must be project:category:category-name category links to categories on this Wikipedia, creating a red link if the category doesn't exist. Without the colon but starting with the prefix category, nothing appears in the saved page.
Examples of link combinations
Technical
A project's own namespace prefix cannot be reused as code for an external project. However, the prefix used for a target project may coincide with the prefix for a project namespace, within that project. As a result, to link to a page in that namespace, use the same prefix twice. For portability across projects, one may want to select a link code that leads to the same target from all projects, for example: MetaWikipedia:wikibooks:Main Page. The "superfluous" "MetaWikipedia:" prevents "wikibooks:" being interpreted as namespace prefix, when the code is used at wikibooks itself, while at Meta the "MetaWikipedia:" is ignored (it is not a namespace prefix and even at Meta itself, it is recognized as code for Meta). The codes above work from all projects; however, the existence detection and the self-link feature do not work on interwiki links.Prefixes
Interwiki links can use prefixes for the project and/or for the language. Without the prefix, links are local, for pages in the same project and the same language. If only a language is given, they go to a page in the same (or similar) project for the specified language: w:en: w:en: pages; a project prefix before the language is better.
More than two prefixes are generally unnecessary; the following examples should work everywhere:
m:, because it is local and then, interprets
en: as w:en:, the prefix for the English Wikipedia. In the second case, the leading en: goes to the English Wikipedia, where the following m: goes straight back to Meta. The second example doesn't work at all, from English Wikipedia w:en: pages, only the third example works everywhere.
In other words, multiple prefixes are evaluated left to right by the relevant Wikimedia servers (project and language). For projects without different languages, like Meta (because Meta is
multilingual by itself), language prefixes can be handled as shorthands for w: plus the specified language:
:pl: interprets the second prefix w:.
For a portable link on that server, it would be a bad idea to use w:, but :pl: does the trick. To test that effect from Meta, the following links should go to the same page:
Interlanguage links
Interlanguage links are links from any page (most notably articles) in one language code:Title These links do not show up in the article, but instead populate the "Languages" list on the sidebar. While they can be theoretically located anywhere in the article, they were typically placed near the bottom.ar:عوالق de:Plankton eo:Planktono es:Plancton fr:Plancton nl:Plankton ja:プランクトン ko:플랑크톤 pl:Plankton pt:Plâncton ru:Планктон simple:Plankton zh:浮游生物界
Interlanguage interwiki links
Inline links to foreign-language Wikiprojects can be made by adding the language code as a prefix: * To link to a Wikipedia article in a particular language inline (as opposed to the links in the sidebar), use :language code:Title :project:language code:Title :language code:project:Title :s:de:Salz :de:s:Salz de.wikipedia.org/wiki/s:Salz, :wikt:fr:sel :fr:wikt:sel en.wiktionary.org/wiki/fr:sel, etc. See § Doubling prefixes for more tips and examples, plus information on doubling with the category prefix.
For language codes, see list of Wikipedias. Remember to put a colon in front of a link starting with a language code prefix, or the saved edit will not show it at all; however, the colon is optional if the link starts with the project code prefix and then has the language code prefix.
The interlanguage link feature works on Wikimedia Commons and Wikispecies, producing links to the Wikipedias. This is not reciprocal, a link from a Wikipedia to Commons or Wikispecies is an in-page link.
More examples
To link from en.Wikipedia to the Chinese language Wikisource page 天問, but without the misleading and distracting appearance of an external link: :Type:Interwiki links versus external links
Disadvantages of interwiki links: * The wikitext is less portable across wikis, because wikis do not always have an interwiki prefix for the same sites and even if they do, the prefixes may differ. * There is no feature to find interwiki links, while searching for an external link can be done with Special:Linksearch (if installed). This is because, while there is an external links table, there is no such thing for interwiki links. The interwiki table only stores the interwiki prefixes with their targets as function of the parameter, not the instances of the links. Using the general text search, to search for interwiki links, is more work for the server and therefore, it may be slow, not up-to-date or in busy hours, disabled. See also: Finding external links to a page. Comparison: *Interwiki links to the same wiki versus internal links
Disadvantages of interwiki links to the same wiki, compared to internal links: * no existence detection * "What links here" works for internal links only Advantages of interwiki links to the same wiki, compared to internal links: * better portability across wikis, provided that the same prefix applies and is not equal to a namespace nameSee also
* Wikipedia:Wikimedia sister projects, a guideline for using Wikipedia's sister projects * m:Templates for linking to sister projects * Templates for linking between the various Wikimedia sister projects ** ** Wikipedia:Template index/Sister projects ** :Interwiki link templates * Help:Interlanguage links, describes how to link between differing foreign language Wikipedias * Help:Menu/Links, table of contents for help pages about links and references * mw:Help:Interwiki linking, help page from