title: why my react code not working?
body: <p>Everyone I am new to <code>reactjs</code> .I don't want to use react-create app . So, I have created two file , but when I am executing it , it does not do any thing . I'm getting blank page. why ?
  <strong>index.html</strong>  </p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html&gt;
  &lt;head&gt;
      &lt;title&gt;&lt;/title&gt;
      &lt;script crossorigin src="https://unpkg.com/react@16/umd/react.development.js"&gt;&lt;/script&gt;
      &lt;script crossorigin src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"&gt;&lt;/script&gt;
  &lt;script src="app.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;div id="app"&gt;&lt;/div&gt;
  
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p><strong>app.js</strong></p>
  
  <pre><code>import React from 'react';
  import ReactDOM from 'react-dom';
  
  
  class Welcome extends React.Component {
    render() {
      return &lt;h1&gt;Hello&lt;/h1&gt;;
    }
  }
  ReactDOM.render(
     &lt;Welcome /&gt;,
    document.getElementById('app')
  );
  </code></pre>