title: How to insure links support Twitter preview?
body: <p>First of all, please note that I searched for a SocialMediaStackExchange to ask this question on, but there doesn't seem to be one.  </p>
  
  <p>Here's what I'm wondering. When posting a tweet to twitter, if it is a youtube link or specific web site's link, then twitter will show an <em>Expand</em> functionality which the user can click to preview the media content right in the Twitter interface.</p>
  
  <p>Does anyone know if this is determined by Twitter or if there is some way I can alter my web site to enable the preview on twitter?</p>
  
  <p>I'd like to make it so when I tweet a blog entry that people can preview the first bit of contents of the article.
  Here's an example: (simply adding the link, displays the preview content shown) In this case it is an article on InfoWorld.</p>
  
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  <p><img src="https://i.stack.imgur.com/ixINl.png" alt="Web link creates preview of content"></p>
  
  <hr>
  
  <p>There's a link on Twitter that explains Expanded Content, but not how to make it happen.
  <a href="https://blog.twitter.com/2012/experience-more-with-expanded-tweets" rel="noreferrer">https://blog.twitter.com/2012/experience-more-with-expanded-tweets</a></p>