1. Tetris
What might come as a surprise to some, will be rather self-evident for others. This simple game, which was released back in 1984, has sold more than 143 million copies! Stacking blocks and making the rows disappear is a concept that is so easy to grasp and yet so challenging at times, that everyone from children to older folks enjoy spending hours playing Tetris. The Tetris franchise is so popular in fact, that an epic science fiction movie based on the franchise is in the works, despite the obvious lack of actual material in the game for such a film.
