Programming Tips - Why doesn't a CSS absolute position work when my page has a DOCTYPE?

Date: 2008aug6 Platform: web Lanuguage: html Q. Why doesn't a CSS absolute position work when my page has a DOCTYPE? A. The DOCTYPE makes it more strict. You probably just need to add "px" on your coordinates. For example... Does NOT work with DOCTYPE:
<div style="position:absolute; left:10; top:10;">Hello</div>
Does work with DOCTYPE:
<div style="position:absolute; left:10px; top:10px;">Hello</div>