A section of a page that consists of a composition that forms an independent part of a document, page, or site.
<article>
<h1>My first article</h1>
<p>Lorem ipsum...</p>
</article>
You would use role=article
on non-semantic elements (not recommended, invalid)
<div role="article">
<h1>My first article</h1>
<p>Lorem ipsum...</p>
</div>
W3C Entry for role=article