The TIME's Person of the Century was Albert EINSTEIN, an 8-letter word. EINSTEIN was a German-born theoretical physicist who developed the theory of relativity, one of the two pillars of modern physics. He is best known for his mass–energy equivalence formula E = mc2, which has been dubbed 'the world's most famous equation'. He received the 1921 Nobel Prize in Physics for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect. His work also had a major impact on the development of atomic energy.