Hints enables you to provide a better UX with respect to links/topics. Some keywords/words, need more explanation or/and external resources to be explained further, if the user needs to know more. Normally, you would achieve this by creating a link/anchor to that resource. Hints, makes it possible for your users to get additional information, about a topic/resource, without leaving your post. Too many links in a post, do spoil the broth.
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