Many sites have a sidebar that includes multiple blocks of navigation and other non-navigation content.
The <nav> elements contained in the new <aside> element. It can be used for typographical effects like pull quotes or sidebars, for advertising, for groups of nav elements, and for other content that is considered separate from the main content of the page.
<aside>
<nav>
<h2>Pages</h2>
<ul> .. </ul>
</nav>
...
<nav>
<h2>Recent comments</h2>
<ul> ... </ul>
</nav>
</aside>
