<!DOCTYPE html>
<html>
<body>
<p style="border: 1px solid black">Hello World</p>
<div style="border: 1px solid black">Hello World</div>
<p>The P and the DIV elements are both block elements, and they will always start on a new line and take up the full width available (stretches out to the left and right as far as it can).</p>
</body>
</html>