Shortened footnotes are used for several reasons: (a) they allow the editor to cite many different pages of the same source without having to copy the entire citation, (b) when full citations are gathered in a separate section the article text is uncluttered and much easier to work with, (c) the full citations can be sorted and alphabetized, and (d) it is easier to edit all the full citations at once. Although list-defined references using REFNAMES also accomplishes (b) and (d), that method treats page numbers differently and does not allow for sorting the citations in published articles.
Please read Help:Footnotes first, as this guide builds upon the methods described there.
In this short example, note that an inline citation such as  links to the shortened footnote under "Notes", which in turn links to the long citation in the References list:
The browser back button or the backspace key can be used to navigate back.
A shortened footnote can be created using standard
<ref> tags, but this will not link to the long citation:
The link is normally created from the authors' last names and the year of publication.
Citations in the References list are usually created with a "long" citation template, both with Citation Style 1 and Citation Style 2 templates. Anchor is automatically created from the authors' last names and the year of publication:
Full citations in the references list may be formatted manually or by use of templates. See the Wikipedia referencing navbox below for various citation styles.
The inline citation should include only the year. The full citation may include the year only or the full date. Most citation templates will extract the year from a full date to form the anchor. If both a date and a year are included, then the date is displayed, but the anchor is formed from the year.
If an author has multiple works in the same year, regardless of whether is a full date or only a year, then duplicate anchors will be generated. To resolve this, suffix the year with an alpha character. For example:
Some sources do not have a single author with a last name, such as a magazine article or a report from a government institution. Options include:
Explanatory or content notes are used to add explanations, comments or other additional information relating to the main content. One of the reasons they may be used is to avoid making the text too long or awkward to read. Such notes may include supporting references.Separate explanatory notes with shortened footnotes and their references
<ref> tags will be automatically displayed in article, user, template, category, help and file pages. To show error messages on talk and other pages, see Help:Reference display customization.
It is also possible to create duplicate IDs for the inline citation, resulting in invalid HTML. See Help:Markup validation for help in validating and resolving issues.
If there is a need to cite two works by the same author published in the same year see more than one work in a year for advice on what to do.