Tetris

Tetris is a free online game in PopGameBox; it is a puzzle with the shapes each consisting of several squares, that are falling down the well. When playing a tetris game, one turns them or moves left and right, trying to arrange the shapes in a line. When a line of squares makes a line from edge to edge, it disappears and all the pieces move down by a square. When the well is filled up, the player loses.