Welcome to Minesweeper, a very smart and wise strategy game. There is a field and you start by clicking on a tile, this will open up a patch of tiles, look around for the tiles with numbers on them. The number on a tile says how many bombs (or mines) are next to that tile, either diagonally, vertically, or horizontally. if you hover over an undug tile and press space you can flag it, this does nothing but put a flag on that tile, this is so you can remember where the mines are. Try to dig out the whole grid without digging a mine!
To save you can press S and receive your save code, and press L to load and paste it. When you die three save codes will be given to you, the continue code just allows you to continue from where you died, the reset code will fully restart but leave the bombs in the same place, and the cheat code will do exactly the same as the continue code but flag all the bombs for you! There is a level editor by pressing 0 and just press S to save and play your level.