Beneath the seemingly innocent exterior of Tetris lurks a game of complex mathematical laws. Here is a quick guide to the ‘Rules of Tetris’.

Each Tetris piece is called a tetrimino (from the Greek ‘tetra’, meaning ‘four’) and is made up of a different configuration of four smaller squares. There are seven tetriminos in total.

Each piece that falls down the screen is randomly chosen from one of these seven types. The player must rotate the falling pieces and slot them together to create a solid horizontal line, which is then cleared from the screen. Fail to clear lines and the pieces start to stack up. If they fill the screen, it’s ‘Game Over’.

Clearing one line at a time is worth the least points, with two or three lines scoring even higher. The ultimate aim, though, is to clear four lines at once (called a ‘Tetris’) for the highest possible score.

However, you can only create a ‘Tetris’ by using the long ‘I’-shaped piece, by arranging pieces in such a way that a vertical gap is left. Skilled players plan ahead by keeping an eye on the ‘Next’ window, which shows the pieces that are coming next.

Bonus points are awarded if you speed up the descent of a piece by pushing down on the +Control Pad. This is easy at first, when the game runs slowly, but at higher skill levels the pieces fall much faster and are hence harder to manoeuvre into the right position.

Such is the unique mathematical nature of Tetris that some thinkers have pondered whether, theoretically, it can be played forever. However, the fact that the blocks appear randomly means that the player is bound to lose eventually, no matter how fast their fingers are!