Page Layout
http://www.usability.gov/pdfs/chapter6.pdf

Usability.gov
2006

Abstract:

All Web pages should be structured for ease of comprehension. This includes putting items on the page in an order that reflects their relative importance. Designers should place important items consistently, usually toward the top and center of the page. All items should be appropriately aligned on the pages. It is usually a good idea to ensure that the pages show a moderate amount of white space—too much can require considerable scrolling, while too little may provide a display that looks too 'busy.' It is also important to ensure that page layout does not falsely convey the top or bottom of the page, such that users stop scrolling prematurely.