An occasional element of Wikipedia entries is a section called "See also". When it appears, it is an alphabetized, bulleted list of links to related Wikipedia articles, found at the end of the main text, just above the "References" section.
Importantly, links included in "See also" should not already appear in the main body of the article. In fact, the purpose of "See also" is to provide notice of relevant topics that didn't make it into the main text.
Also important, and not unlike the "External links" section, go easy. Think about the reader's time: by selecting only a few links, it suggests the included are worth their time. For the same reason, don't link to disambiguation pages.
And don't forget: not every article needs a "See also"! After all, the better-written an article is, the less likely it will need this section at all.