The goal of the game is to uncover all the squares that do not contain mines without clicking on a square with a mine underneath. The location of the mines is discovered by a process of logic. Some squares contain numbers (1-8), each being the number of mines adjacent to the uncovered square. To help avoid hitting a mine, the location of a suspected mine can be marked by flagging it. The game is won once all blank squares have been uncovered without hitting a mine. (wikipedia.org)