Wikipedia:Only make links that are relevant to the context
Appropriate links provide instant pathways to locations within and outside the project that are likely to increase readers' understanding of the topic at hand. Whenever writing or editing an article, it is important to consider not only what to put in the article, but what links to include to help the reader find related information, as well as which other pages should carry links to the article. Care should be taken to avoid both underlinking and overlinking, as described below.
This page provides guidelines as to when links should and should not be used, and how to format links. Detailed information about the syntax used to create links can be found at Help:Link. The rules on linking applicable to disambiguation pages are set out in the disambiguation style guide.
An article is said to be underlinked if words are not linked that are needed to aid understanding of the article. In general, links should be created to:
Do not be afraid to create links to potential articles that do not yet exist (see § Red links below).
If you feel that a link does not belong in the body of an article, consider moving it to a "See also" section.
A good question to ask yourself is whether reading the article you're about to link to would help someone understand the article you are linking from. Unless a term is particularly relevant to the context in the article, the following are not usually linked:
Do not link to pages that redirect back to the page the link is on (unless the link is to a redirect with possibilities that links to an appropriate section of the current article).
The function of links is to clarify, not emphasize; do not create links in order to draw attention to certain words or ideas, or as a mark of respect.
Generally, a link should appear only once in an article, but if helpful for readers, a link may be repeated in infoboxes, tables, image captions, footnotes, hatnotes, and at the first occurrence after the lead. Duplicate links in an article can be identified by using a tool that can be found at User:Ucucha/duplinks. However, in glossaries, which are primarily referred to for encyclopedic entries on specific terms rather than read from top to bottom like a regular article, it is usually desirable to repeat links (including to other terms in the glossary) that were not already linked in the same entry .
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