Template:Anchor - Wikipedia

1. {{anchor|foo}}

could be linked to with [[#foo|...]] from within the same article,

or it could be linked to with [[articlename#foo|...]] from other articles and from redirects.

2. Anchors can be more suitable for inter-article linking than section titles are. For example,

== {{anchor|foo}} Section title ==

Here, links via [[articlename#foo]] would remain valid even if the section were renamed.

3. The template can be used to create up to ten anchors with a single call. For example,

{{anchor|foo|bar|baz}}

will create three anchors that can then be linked to with [[#foo]], [[#bar]] and [[#baz]].

Specifying more than 10 anchors will cause an error message to be displayed.

Anchor names that contain # (hash), | (pipe), = (equal) will not work as expected. However, the latter can be worked around with {{=}}; a redirect with "=" in its name will link properly to an anchor with {{=}}. Markup code such as <sup></sup> and <sub></sub> (superscript and subscript) cannot be used. Most other characters, including white space and punctuation, are not a problem.
The template can create a maximum of 10 anchors. Specifying more than 10 anchors will result in an error message.
Putting each anchor name on separate lines, for example

{{anchor

|humpty
|dumpty}}

will probably not work as expected.

Anchor names should be unique on a page, and should not duplicate any heading titles. Duplicate anchors won't work as expected since the #links go to the first anchor with that name. Duplicate anchors also result in invalid HTML, so you can check for duplicate anchors by consulting the W3C Markup Validation Service.
If the template is added to a section title then the code will appear in the edit summary when that section is edited, as in "/* {{anchor|Issues}}Limitations */ New issue". This can be fixed by deleting the template code from the edit summary before the changes are saved.