Newbie wants to know: How to rotate content?

You know how on pay sites the newest content is usually first, pushing older content down the page? How do they do that?

I know that on a blog or CMS this is automatic, but on a page you create in Dreamweaver or another HTML editor, how can you accomplish this trick, other than manually moving everything around? Or is this only possible with a blog, CMS or custom script?

For example, on my Dreamweaver page with a grid that has 3 rows and 5 columns, it's kind of a hassle if I want to put something in the top left column box and have everyhing else in the grid slide down, with the item in box 15 moving off to another page with another grid.

I wonder if there is an easier way to do this so if anyone knows how I'd appreciate the info.

Thanks!