title: app.set and app.engine in Express
body: <p>I am following a <a href="http://code.tutsplus.com/tutorials/introduction-to-express--net-33367">Node.js tutorial</a>.</p>
  
  <p>Two lines for which I am not sure are:</p>
  
  <pre><code>app.set('view engine', 'html');
  app.engine('html', hbs.__express);
  </code></pre>
  
  <p>I checked the <a href="http://expressjs.com/3x/api.html#app.set">documentation</a> for <code>app.set</code> and it only tells me:</p>
  
  <blockquote>
    <p>Assigns setting name to value.</p>
  </blockquote>
  
  <p>But my question is what's the relevance of using this. I googled it and wherever <code>app.engine</code> is used <code>app.set</code> is called before.</p>
  
  <p>Let me know the significance of using <code>app.set</code> before the <code>app.engine</code>.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>I found the following line, but I am still unclear as I am using template engine very first time:</p>
  
  <blockquote>
    <p>But we can tell Express to treat HTML files as dynamic by using the <code>view engine</code> directive, you see above. </p>
  </blockquote>