Early floppy-disk copies of IBM PC Tetris first circulated in Moscow. After Alexey Pajitnov and his collaborators adapted the game for the IBM PC, copies spread through the Dorodnitsyn Computing Center and Moscow’s computer circles.
The IBM PC version was developed after the original Elektronika 60 implementation. Pajitnov worked with Dmitry Pavlovsky and the teenage programmer Vadim Gerasimov, who helped adapt the game using Turbo Pascal. The IBM PC’s display supported a more recognizable visual presentation than the text-based original.
These floppy disks were not initially a commercial product. People copied and shared the game freely, and its popularity expanded from Moscow to other Soviet cities and then into Eastern Europe. By 1986, Tetris was reportedly familiar to nearly everyone in Moscow who had access to an IBM computer.
Moscow is sometimes confused with Budapest because Robert Stein encountered Tetris after it had reached Hungary. That was a later stage in the game’s international journey: Hungarian programmers had made ports, and Stein’s discovery there led to the licensing deals that eventually brought Tetris to Western publishers.