Kristen Nygaard (27 August 1926 – 10 August 2002) was a Norwegian computer scientist, programming language pioneer, and politician. Internationally, Nygaard is acknowledged as the co-inventor of object-oriented programming and the programming language Simula with Ole-Johan Dahl in the 1960s. Nygaard and Dahl received the 2001 A. M. Turing Award for their contribution to computer science. Early life and career Nygaard was born in Oslo and received his master's degree in mathematics at the University of Oslo in 1956. His thesis on abstract probability theory was entitled "Theoretical Aspects of Monte Carlo methods". Nygaard worked full-time at the Norwegian Defense Research Establishment from 1948 to 1960, in computing and programming (1948–1954) and operational research (1952–1960). From 1957 to 1960, he was head of the first operations research groups in the Norwegian defense establishment. He was cofounder and first chairman of the Norwegian Operational Research Society (1959–1964). In 1960, he was hired by the Norwegian Computing Center (NCC), responsible for building up the NCC as a research institute in the 1960s, becoming its Director of Research in 1962. Object-oriented programming With Ole-Johan Dahl, he developed the initial ideas for object-oriented programming (OOP) in the 1960s at the Norwegian Computing Center (Norsk Regnesentral (NR)) as part of the Simula I (1961–1965) and Simula 67 (1965–1968) simulation programming languages, which began as an extended variant and superset of ALGOL 60. The languages introduced the core concepts of object-oriented programming: objects, classes, inheritance, virtual quantities, and multi-threaded (quasi-parallel) program execution. In 2004, the Association Internationale pour les Technologies Objets (AITO) established an annual prize in the name of Ole-Johan Dahl and Kristen Nygaard to honor their pioneering work on object-orientation. This Dahl–Nygaard Prize is awarded annually to two individuals that have made significant technical contributions to the field of object-orientation. The work should be in the spirit of the pioneer conceptual and/or implementation work of Dahl and Nygaard which shaped the present view of object-oriented programming. The prize is presented each year at the ECOOP conference. The prize consists of two awards given to a senior and a junior professional. He conducted research for Norwegian trade unions on planning, control, and data processing, all evaluated in light of the objectives of organised labour ([1971–1973), working together with Olav Terje Bergo. His other research and development work included the social impact of computer technology, and the general system description language DELTA (1973–1975), working with Erik