This article describes the history of creation of the first digital computer in Russia. It started in the electronic systems laboratory of the Energy Institute of the USSR Academy of Science, led by I.S. Brook. The first developer was N.Y. Matyukhin. The computer M-1 consisted of arithmetic unit, main program sensor (control device), internal memory of two types (fast one – on cathode-ray tubes and the slow one – on magnetic drum), and an input/output device using telegraph alphanumeric equipment. By the end of 1951, for the first time in the world, the M-1 started working in experimental mode with fast-acting storage device made on common LO-737 cathode-ray tubes. The computer successfully passed complex tests and was switched to operational mode. For the first 1.5 years, it had been the only computer in the USSR.