title: JavaScript this.checked
body: <p>In JavaScript, if we write the following for example:</p>
  
  <pre><code>var c = this.checked;
  </code></pre>
  
  <p>What is <code>checked</code> here? Is it just a <strong>state</strong> that tells us if a checkbox for example is checked or <em>not</em>? So, can we use it to check that the checkbox is also not checked?</p>