Les Belady

László "Les" Bélády (born April 29, 1928 in Budapest) is a Hungarian computer scientist notable for devising the Bélády's Min theoretical memory caching algorithm in 1966 while working at IBM Research. He also demonstrated the existence of a Bélády's anomaly. During the 1980s he was the editor-in-chief of the IEEE Transactions on Software Engineering.

Bélády earned B.S. in Mechanical Engineering, then an M.S. in Aeronautical Engineering at the Technical University of Budapest. He left Hungary after the Hungarian Revolution of 1956. He worked as a draftsman at Ford Motor Company in Cologne and as an aerodynamics engineer at Dassault in Paris. In 1961 he immigrated to the United States, where he joined International Business Machines and did early work in operating systems, virtual machine architectures, program behavior modeling, memory management, computer graphics, Asian character sets, and data security. In the 60s and 70s he primarily lived in New York City with stints in California and England.