I'm working on a big website at the moment and the designers are talking about making a facebook-like content area.. By this they mean that they want to keep the header loaded at all times and then only reload the content area when a link is clicked. Still we want to change the url to keep the framework working as well when accessing some page directly.
I'm not sure how to explain this any further - check out facebook and take a close look at the header whenever you navigate to another page..
Thanks..