Miyamoto Musashi is a prominent figure in Bushido. He is the author of "The Book of the Five Rings". It is a book on the Japanese Way of the Sword. His book offered the warrior a set of guidelines to follow if they wanted to use the sword properly and remain victorious in battle. Little is actually known about this influential man. According to research, he killed his first man when he was thirteen years old. For a large portion of his life, he was refining his techniques with the sword.