You can use this to, for example, to link from BazBar to "FooBar/SubPage",
or from BazBar/SubPage to "FooBar/SubPage".
+
+You can also use "/" at the start of a link, to specify exactly which page
+to link to, when there are multiple pages with similar names and the link
+goes to the wrong page by default. For example, linking from
+"FooBar/SubPage" to "/OtherPage" will link to the "OtherPage" in the root
+of the wiki, even if there is a "FooBar/OtherPage".
+
+Also, if the wiki is configured with a userdir, you can link to pages
+within the userdir without specifying a path to them. This is to allow for
+easy linking to a user's page in the userdir, to sign a comment. These
+links are checked for last of all.