Among the most iconic puzzle games ever created is the block-crunching Tetris. Devised in the Soviet Union by a Russian engineer named Alexey Pajitnov, and holds the distinction of being the first game exported to the United States from the USSR. The game first arrived on the Commodore 64 and the IBM PC, and has spawned versions on just about every computer system ever built, including cell phones and even pocket calculators. The game has sold more than 170 million copies since it was first released, the majority of which have been paid-for downloads.During development, Pajitnov originally envisioned a game which employed blocks of five squares rather than four, but it was decided that four would be just complex enough for a child to grasp. Another wise decision came as a result of the limitations of the text-based screen he was working with. When a line was completed in the original version, it didn’t disappear – it stayed on the screen indefinitely. When this was changed, so to did a core gameplay mechanic.It was a business decision that catapulted Tetris into popular consciousness. Nintendo agreed in the late 1980s to bundle the game with every Game Boy console sold. At the time, handheld gaming had yet to take hold, and it took the inclusion of this puzzle classic to ensure the Game Boy’s success.Nowadays, there are countless variants on the classic Tetris formula, and countless ways to play the original. Here at Gamepix, we provide Tetris games in unblocked HTML5, allowing you to play them on any device equipped with a web-browser. It’s a tried-and-trusted puzzle classic, so why not spend some more time with it?