Tetris is a tile-matching puzzle video game, originally designed and programmed by Russian game designer Alexey Pajitnov. It was released on June 6, 1984, while he was working for the Dorodnitsyn Computing Centre of the Academy of Science of the Soviet Union in Moscow. He derived its name from the Greek numerical prefix tetra- (all of the game's pieces contain four segments) and tennis, Pajitnov's favorite sport.
Tetris was the first entertainment software to be exported from the Soviet Union to the US, where it was published by Spectrum HoloByte for Commodore 64 and IBM PC. The Tetris game is a popular use of tetrominoes, the four-element special case of polyominoes. Polyominoes have been used in popular puzzles since at least 1907, and the name was given by the mathematician Solomon W. Golomb in 1953. However, even the enumeration of pentominoes is dated to antiquity.
The game (or one of its many variants) is available for nearly every video game console and computer operating system, as well as on devices such as graphing calculators, mobile phones, portable media players, PDAs, Network music players and even as an Easter egg on non-media products like oscilloscopes. It has even inspired Tetris serving dishes and been played on the sides of various buildings.