When the contained (red) item is set to absolute it positions itself relative to it's parent element *if the parent element is itself positioned* as in the following example. However, if you take out the position property in the parent element the contained element will position itself relative to the screen. This will also happen if you take the contained element out of the parent container.

It's important to understand one fact when positioning elements with CSS: the position is always relative to the nearest positioned parent element. When people first start dabbling with CSS, there's a common misconception that position: absolute; positions right up to the page root. I think this stems from the fact that, yes, without any parent elements with position styles - this is true. It traverses up the DOM tree, not finding any positioned elements, and settles on the root of the page. http://taitems.github.com/Front-End-Development-Guidelines/