CSS3 Flexible Box Model
Peter Gasston erklärt das Flexible Box Model.
I should reiterate that much of what is possible with Flex Box can already be achieved with existing CSS properties such as float, margin and position. The difference is that Flex Box has been created with the express intent of laying out web pages so it makes that task much, much easier.
Here’s a quick summary of what it does: equally distributes space between elements without the need for you to make complex calculations; enables you to make equal-height columns and to vertically align elements within their parent; enables you to change the order in which elements are displayed, regardless of their order in the DOM tree; removes the need to use the float property for layouts. In short, it enables you to do all of the stuff that you’ve had to hack around in the past. Sounds perfect!
Leider mangels Support im IE zur Zeit nur eingeschränkt nutzbar.