Sun Tzu was a Chinese author of The Art of War, an immensely influential ancient Chinese book on military strategy. He is also one of the earliest realists in international relations theory. The name Sun Tzu ("Master Sun") is an honorific title bestowed upon Sun Wu, the author's name. The character wu, meaning "military", is the same as the character in wu shu, or martial art. Sun Wu also has a courtesy name, Chang Qing. Source: Wikipedia