{{[[Template:{{{1}}}|{{{1}}}]]}} is designed to be used to create shortened footnotes, a citation style which pairs a short, author-date citation in a footnote with a complete citation in the references section at the end of the article (see example below). This citation style is used to reduce clutter in the edit window and to combine multiple citations to the same source.
Common problems and known workarounds are given in the section possible issues section below.
There are several other templates that are designed for use with shortened footnotes. They differ slightly in the way they format the author-date citation and how much of their functionality is automated. A full list of these related templates is below.
Note that the use (or even non-use) of these templates is an element of citation "style", and adding or removing them in articles with an established style should be consistent with that style. See WP:CITEVAR.
Also note that inline use of these templates, i.e. use of {{harv}} without <ref>...</ref> tags around it, was deprecated in September 2020. See also WP:PAREN.