Klára Dán von Neumann (born Klára Dán; 18 August 1911 – 10 November 1963) was a Hungarian-American mathematician, self-taught engineer and computer scientist, noted as one of the first computer programmers. She was the first woman to execute modern-style code on a computer. Klára made significant contributions to the world of programming, including work on the Monte Carlo method, ENIAC, and MANIAC I. She was introduced to a lot of her work through her husband, John von Neumann.
