Linking articles: the internal link
Internal links are a great way to alert users to pertinent information. However, remember that excessive linking can detract from an article. Only create links that are relevant to the context of the article. Internal links are created by placing double brackets around the word you wish to link, for example: [[SubjectX]]. You can link to a specific section by adding the # sign and the name of the section after the article name. For example: [[SubjectX#The beginning]].
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Help:Section linking