title: What are "data-require" "data-semver" in HTML files?
body: <p>I have seen tags like this in HTML. What are these attributes?</p>
  
  <p><strong>This is NOT a duplicate of the <code>data-*</code> question.</strong></p>
  
  <p><strong>Edit:</strong>
  I am looking for these two specific attributes, not <code>data-*</code> in general, nor data-require<strong>d</strong>, as Google suggests. If you search the web, you can find these attributes are used in many places. I guess this is some like of dependency management software? </p>
  
  <pre><code>&lt;link data-require="bootstrap-css@*" data-semver="3.0.0" rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css" /&gt;
  
  &lt;script data-require="angular.js@1.1.x" src="https://ajax.googleapis.com/ajax/libs/angularjs/1.1.5/angular.js" data-semver="1.1.5"&gt;&lt;/script&gt;
  &lt;script data-require="ui-bootstrap@0.5.0" data-semver="0.5.0" src="http://angular-ui.github.io/bootstrap/ui-bootstrap-tpls-0.6.0.js"&gt;&lt;/script&gt;
  </code></pre>