Help:Footnotes

This page explains how to create footnotes on pages. Footnotes are used most commonly to provide references in articles, although they have other uses as well. They are generated using the following tags in the editable text of a page: ... within the text, and or   at the end where the footnote list is to appear.

The most common use of footnotes in articles is to provide inline citations to reliable sources, although footnotes can also be used for other purposes.

Overview
The footnoting system involves two elements:
 * Footnote markers. These are links, usually in the form [1], [2] , etc. Clicking on a footnote marker will take you to the correspondingly numbered footnote.
 * The footnotes themselves. These appear in a list (usually placed near the end of the article), and include links back to the corresponding footnote markers.

Footnote markers are generated using  tags. The list of footnotes is generated using the tag, or the more commonly used corresponding References template, placed in the editable text at the point where the footnotes are to appear. The text of a footnote is placed between opening and closing  tags, at the point where the footnote marker is to appear. If the page contains footnote markers but no footnote list, a red cite error message will appear.

Creating a footnote marker
At the point in the page text where the footnote marker is to appear, enter the text of the footnote and put the two pieces of coding before and after the footnote-text, like this:

This will create a footnote marker (automatically numbered). The footnote text itself will appear in the footnote list, generated as described below. If there is no footnote list code, a red warning message will appear, reminding you to write the code that generates the list.

You can include formatting and links in a footnote in the usual way, although certain features, such as the pipe trick and template substitution, will not work in footnotes.

Multiple references to the same footnote
It is possible to refer to the same footnote more than once, in other words to generate several footnote markers, all with the same number, which link to the same footnote. To achieve this, named footnotes (named references) are used.

A footnote is named using the  parameter of the  tag. Choose a name (such as "Perry"), and then at one of the footnote marker points (it makes sense to choose the first), enter the footnote like this:

Then you can create another identical marker linking to the same footnote from any other point in the text, by entering the following (note the final slash):

The footnote name is internal and will not be displayed anywhere when the page is viewed. Footnote names are case sensitive and may not be an integer numeral. The quotes are optional unless the name or group includes a space, or certain punctuation marks and other characters. It is recommended that names be kept simple and restricted to the standard English alphabet and numerals.

Be careful when deleting text containing named footnotes – if you delete the instance which contains the footnote text, without replacing it elsewhere, you will break other instances of the same named footnote on the page. Error messages will be generated if the named footnotes used have not been properly defined.

Creating the footnote list
At the point where you want the text of the footnotes to appear (usually at the end of the article in a section titled "References" – see the layout guideline), write the following code:

A commonly used alternative is the References template:

The footnote list must come after all the footnote markers.

If a footnote list is generated but there are no footnotes on the page, the list will simply appear empty (no warning or error message is displayed).

What it looks like
When a page with footnotes is displayed in a browser, the  tags in the main text are converted to auto-numbered superscripts, like this:

The only reference to LibreOffice for Starters. The first reference to Perry's Handbook. The second reference to Perry's Handbook and to another, related book. The only reference to Linux in a Nutshell. And third reference to Perry's Handbook.

Clicking on a numbered superscript takes you straight to the text of the corresponding footnote.

The tag or References template is expanded to show the text of the footnotes against their corresponding numbers, like this:

For single-reference footnotes, clicking on the arrow ( ↑ ) takes you back to the footnote marker in the main text. For multiple-reference footnotes, the links back to the main text are distinguished by superscripts ( 2.0 2.1 2.2 etc.). Clicking on a superscript takes you to the corresponding marker in the main text.