title: Client side rendering React
body: <p>I am new to React(Angular background) and trying to do client side rendering with react.
  Following index.html which is sent by express application:</p>
  
  <pre><code>&lt;html&gt;
      &lt;head&gt;
          &lt;title&gt;My Web&lt;/title&gt;
          &lt;link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.7/css/bootstrap.min.css"&gt;
          &lt;script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/react/15.4.1/react.min.js"&gt;&lt;/script&gt;
          &lt;script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/react/15.4.1/react-dom.min.js"&gt;&lt;/script&gt;
          &lt;script type="text/javascript" src="/static/src/js/firstComponent.js"&gt;&lt;/script&gt;
      &lt;/head&gt;
  
      &lt;body id="mainBody"&gt;
      &lt;/body&gt;
  
  &lt;/html&gt;
  </code></pre>
  
  <p>Here is the react component file(firstComponent.js):</p>
  
  <pre><code>var FirstComponent = React.createClass({
      'render': function(){
          return &lt;h1&gt; Hello&lt;/h1&gt;;
      }
  });
  
  ReactDOM.render(&lt;FirstComponent /&gt;, document.getElementById('mainBody'));
  </code></pre>
  
  <p>But on loading the page, react does not seems to work. What is wrong here?</p>