Invented the APL computer programming language
Iverson grew up on a farm in Alberta and like many farm kids he had to drop out of school to work. He was in the Royal Canadian air force during the war, and did not go to university until afterwards. He became Assistant Professor of Applied Mathematics 1955-1960 at Harvard. He developed a new notation for operations on numeric arrays and IBM created an interpreter to execute expressions in Iverson’s notation. He joined IBM and in 1962 published a description of his notation in A Programming Language (APL). This language challenges conventional algebraic syntax but is compact, simple and easy to learn. Recently, and up until his death Iverson began and worked on the Jay Language. Iverson wrote a book called Math for the Layman. In 1970 Iverson was named an IBM Fellow.