Today we see a video that specifically explains something IM Danny Rensch has referred to a few times during his Pawn Structure 101 series as "Opening Evolution"... The main idea being that when you understand the structure and "philosophies" of a position, this enables you to understand how the position/opening is evolving in terms of modern theory. "White improves", then "black improves on the improvement", and then "white..." well you get the idea! Full video available at http://www.Chess.com/videos