Accessibility is treating everyone, no matter what their ability, the same
Provides the framework for the information on the page. It can indicate their position in the heirarchy of the document and the ways they can interact with the different elements of the page, as well as providing emphasis to textual content in the right places
<ul>
<li>Menu Item 1</li>
<li>Menu Item 2</li>
<li>Menu Item 3</li>
</ul>