title: Target container is not a DOM element in ReactJS
body: <p>I just started to learn <strong>ReactJS</strong> and I wrote my first code successfully. When the same pattern came to the component thing I am getting a error mentioning <strong>_Invariant Violation: <em>registerComponent(...): Target container is not a DOM element.</em></strong> in the console. I am using react and babel cdn instead of downloading and importing.</p>
  
  <pre><code>&lt;div id="=f_compo"&gt;&lt;/div&gt;
  &lt;script type="text/babel"&gt;
      var compo= React.createClass({
          render: function(){
              return (&lt;h3&gt;This is a simple component&lt;/h3&gt;);
          }
      });
      ReactDOM.render(&lt;compo/&gt; ,document.getElementById('f_compo'));
  &lt;/script&gt;
  </code></pre>
  
  <p>This was my <strong>index.html</strong> code (I removed the cdn links in the head tag because of the error while posting the question) and <em>following thing</em> is the error that I am receiving.</p>
  
  <p><strong>error:</strong></p>
  
  <p>_invariant
  _registerComponent
  _renderNewRootComponent
  wrapper
  <em>renderSubtreeIntoContainer
  render
  wrapper
  
  i
  r
  o
  u
  f
  </em></p>
  
  <p>Since there were few solutions in the google I need a clear explanation mentioning <strong>Why this kind of error occur?</strong> and <strong>How it can be solved in formal manner?</strong></p>