Even as a young boy, Muhammad Ali knew that he wanted to do great things in his life, and make changes in the world. By the time he was eighteen, Ali was an Olympic Champion in boxing, and he went on to be World Champion three times. But Ali's fights were not just in the boxing ring. He fought for other things too: for peace, for black people's rights, for the sick, and for those in need. This is the story of how he became The Greatest.