Check, checkmate and stalemate

So what is the difference between the three concepts found in the title? Let's take a look:

Check means that your king is under attack from an enemy piece (or pieces in the case of a double check) and that you have to do something about it. There are three possible things to be done: firstly, move the king; secondly, block the check with one of your pieces and thirdly, capture the enemy piece giving that annoying check.

Checkmate: If a player's king is in check and he can't do any of the three things mentioned above, that means that he is checkmate and that he has lost the game.

Stalemate: A player whose turn it is to move but who has no legal move and whose king is not in check, is stalemate. The game then ends in a draw. So what do I mean when I say no legal move? It means that the player has no piece which can move. It usually happens when the player only has the king left, but he could also have for example a blocked pawn. A stalemated player is usually very happy since he gets a draw out of an otherwise lost game (it's often a bit of luck, a bad mistake from the winning side often causes stalemate). Consequently the stalemate is quite frustrating for the player who was winning, but then the game suddenly ends in a draw. A good endgame tactic in a lost position can sometimes be (depending on several factors, like the position, time etc.) to try to play for a stalemate. It doesn't always work, but a well timed sacrifice can make all the difference...

Diagrams are an excellent help in understanding all of this, so here are a few:

Check. The black king can move out of the check. Check. The black king has e8 and g8 to choose from.

Check. The black king can go to e8. Check. The black king can simply capture the queen.

Checkmate. The black king cannot capture or escape. Checkmate. The black king has nowhere to run.

Checkmate. The white king can't get out of check.

Checkmate. The white king can't take the queen because she's protected by the bishop.

Stalemate if it's black to move. He has no legal move (the king can't go to any square because they're all protected by white; e7, e8 and g8 by the queen, g7 by the king and f7 by both of them) and his king is not in check.

Stalemate if it's black to move. He has no legal move and his king is not in check.

Stalemate if it's black to move. He has no legal move and his king is not in check. By the way, White really should have done better and won this game!