title: Event vs CustomEvent
body: <p>I was wondering, what is the purpose of <code>CustomEvent</code>, because it can be easily emulated by good old <code>Event</code>.</p>
  
  <p>So, what is the difference between:</p>
  
  <pre><code>var e = new Event("reload");
  e.detail = {
      username: "name"
  };
  element.dispatchEvent(e);
  </code></pre>
  
  <p>and</p>
  
  <pre><code>var e = new CustomEvent("reload", {
      detail: {
          username: "name"
      }
  });
  inner.dispatchEvent(e);
  </code></pre>
  
  <p>Why does <code>CustomEvent</code> exist if it is easy to attach custom data to ordinary Event object?</p>