nested_list

Here's a FAQ: Why won't my nested list validate? This one comes up surprisingly often in various Net fora.

If the W3C Validator gives you the following message:

  Error: element "li" not allowed here; possible cause 
  is an inline element containing a block-level element.

It's probably because the nested <ul> isn't contained within an <li>. Nested lists should be structured like this:

<ul>
  <li>1</li>
  <li>2
    <ul>
      <li>2.1</li>
      <li>2.2</li>
    </ul>
  </li>
  <li>3</li>
</ul>