This paper describes activities developed in Argentina between 1956 and 1966 related to the computer and that were coincident with the arrival of the first machines in the country. It deals, particularly, with the work of the mathematician Manuel Sadosky (1914- 2005) in the University of Buenos Aires, who was responsible for the first university computer, the first applied mathematics laboratory, the first computer career, and the first professional computer society in Argentina. The construction of experimental computers and the first imported business computers are also mentioned in this paper.