A game anyone can pick up and play.
The objective of the game is to make rows of blocks from pieces that continously fall down,without leaving any spaces.Everytime you make a row of blocks,those blocks will disappear.If the stack of blocks you're dealing with touches the top of the screen,you lose.As your score/level gets higher,the pieces start coming down faster,making you problem solve quicker and making you plan ahead more seriously.
The formula is one that's so playable,and people love it even after more than 20 years since it was invented,which is why the game has appeared on so many consoles and computers.Developers have tried to release new versions of Tetris and they try to change the formula by adding new pieces,or new rules,but often by doing that,they spoiled what is already a great formula.
The game is so loved,developers still release the game on modern consoles,and just add new backgrounds and music.
The Russian music in the game helps add an intellectual,sophisticated feel to the game.
And like someone said,Tetris will still be around and played by people long after all of us are long gone.