A condition affecting web pages or web sites where hyperlinks gradually fail to connect to a live resource over time. Either links become less relevant over time, or they have ceased to exist. When an author adds a link to an outside web page, it is not possible to guarantee the link will always function. For link pages that have moved, some can be kept updated over time but often Web content moves without notice or automatically forwarding the user to the new site.
Linkrot is very common and requires attention and perseverance to keep it at bay. A number of tools exist for webmasters to use on their own website, which checks outside links and reports on broken links. However, persistance is not guaranteed, even for the most enthusiastic of webmasters, as real life catches up and other concerns require attention.
For a wiki, one way for one to drastically reduce the amount of linkrot is to ensure that all heavy linking is done on topics of regular interest. For example, an reader who uses the wiki like a personal bookmark manager will always be keen on keeping frequently referred-to links updated, so they themselves will be compelled to make corrections. Commonly visited topics of interest will find themselves regularly referred to and added on, ultimately more up-to-date than those wiki pages of less frequent interest.