To add an internal link, enclose the name of the page you want to link to in double square brackets. When you save the page, you'll see the new link pointing to your page. If the page exists already it is displayed in blue, if it does not, in red.
Selflinks to the current page are not transformed in URLs but displayed in bold.
(If you really want to link to the current page, use an anchor (see below), or [[#top|current page]] which always links to the top.)
The first letter of the target page is automatically capitalized, unless otherwise set by the admins, and spaces are represented as underscores (typing an underscore in the link will have a similar effect as typing a space, but is not recommended, since the underscore will also be shown in the text).
To add an external link, enclose the URL followed by space and the name of the page you want to link to in single square brackets. When you save the page, you'll see the new link pointing to your page, with an arrow icon after it to show that it was coded with single bracket external link syntax, and thus may lead to another site.
To avoid that effect, put the URL between <nowiki>, like this:
To get this:
Interwiki links are links with the internal link markup to a website registered in advance. For example, you can link to the Sunflower article on http://en.wikipedia.org by typing [[wikipedia:Sunflower]], which will result in a link wikipedia:Sunflower. This is because http://en.wikipedia.org/wiki/ is registered to your wiki by default with the prefix of wikipedia. This link may not work properly, if the admin of your wiki has changed the setting. Unlike internal links, interwiki links do not use page existence detection, so an interwiki link will appear blue even if the page does not exist on the remote wiki.
Similar to internal page links, you can create piped links, with alternate link label, e.g. [[wikipedia:Sunflower|big yellow flower]], this is the link big yellow flower.
Basically this is an abbreviation for longer URLs. A very similar link could be created as a normal external link by typing [http://en.wikipedia.org/wiki/Sunflower big yellow flower], but interwiki links allow you to type out an easy and compact link, almost as if you are linking to a page on your own wiki.
If your wiki has other language versions, you may find “interlanguage links” in the sidebar, just below toolbox in the box named “其他语言.”
Interlanguage links behave similarly to interwiki links, except that they are listed in the sidebar. To create an interlanguage link from a page, just type [[language prefix:pagename]] wherever you like in the page; the language prefix is the prefix specified at your wiki for the other language version (typically the ISO 639-1 language code).
If you want to make the interlanguage link appear in the content of the page, you can add a colon before the language prefix: