title: What is [Serializable] and when should I use it?
body: <p>I found out that some classes use the <code>[Serializable]</code> attribute.</p>
  
  <ul>
  <li>What is it?   </li>
  <li>When should I use it?   </li>
  <li>What kinds of benefits will I get?  </li>
  </ul>