And maybe the biggest single innovation that changed the world, for better or worse, was the use of gunpowder, which there's some use in the late Tang, but it really starts to get perfected during the Song Dynasty. Now the Song Dynasty is eventually overthrown in the 13th century by the Mongols, and they are able to establish the Yuan Dynasty, with Kublai Khan being the first emperor of it, grandson of Genghis, or Genghis Khan. Now they are eventually overthrown in the 14th century by the Ming Dynasty. The Ming Dynasty is once again ethnically Han, and some of the most famous attractions that are associated with China today really came about from the Ming Dynasty. This is the Forbidden Palace, the imperial residence during the Ming and Qing Dynasties in Beijing. This is the Great Wall of China, and even though the history of the Great Wall of China goes a good ways back, even to the Zhou and Warring States periods, much of what you now see as the Great Wall, a lot of this brickwork, was built during the Ming Dynasty. And then the last true dynasty of China is the Qing, and the Qing Dynasty is again, to some degree, foreign rule.