Checkmate and Stalemate are often confusing to new players. Distinguishing between them is one of the most important concerns for beginners.
Have a look at these two positions with Black to move. In both cases Black has no legal moves, so the game is over. But one is a draw, and one is a win for White.
Why is the second position checkmate? The difference is literally in the name. The black king is in check, thus "check" mate. In the first position the black king is NOT in check, therefore not in "check" mate.
You might say "You can't have checkmate without check" or "Checkmate starts with check".
It's a very simple distinction, but one which is often forgotten by inexperienced players. Many half-points have been lost by players intending to checkmate but stalemating instead!For more details also see Checkmate and Stalemate. Now test your understanding on the following positions. In each diagram White has just moved, and you must decide if it is Checkmate, Stalemate, or neither. Try to work out the answer yourself before clicking the "Reveal" button to verify.