Written 2500 years ago, The Art of War is the oldest military treatise in the world, a classic study of competition and rivalry that has been utilized by soldiers ever since. Napoleon studied its strategies and tactics. It is required reading for intelligence personnel in the United States Marine Corps. "Warriors" of Wall Street and in corporation cultures rely on it for guidance. It's even been rumored to help players win at the board game Risk. This 1910 translation by the British Museum's Lionel Giles is the most popular one available, a highly readable version of this still startlingly relevant text.