Stephen Wolfram's PR team/Stephen Faust · CC BY-SA 3.0

Built Mathematica, the computer algebra system that became a standard tool across science and engineering, then followed it with the Wolfram Alpha answer engine, applying the same computational approach to general knowledge queries. A physicist and computer scientist by training, he founded and leads Wolfram Research as its chief designer, and was named a fellow of the American Mathematical Society in 2012. His research spans computer algebra and theoretical physics.