What is the difference between check and checkmate?

Check means the king is attacked and you must deal with it this move, by moving the king, blocking the line or capturing the attacker. Checkmate means none of those three answers exists. The game stops there: nobody ever takes the king off the board. In writing, a plus sign marks check and a hash mark marks mate.

What is the least material you need to force checkmate?

A single rook, or a single queen, plus your own king. Two bishops also do it, and so do bishop and knight, though that one is much harder. A lone bishop or a lone knight cannot mate a bare king at all, no matter how badly the defender plays, so those endings are drawn as soon as the last pawn goes.

How long can it take to force mate with a queen or a rook?

Ten moves at most with king and queen, sixteen at most with king and rook, counting from any legal starting position with best play. Beginners usually take longer, which is fine, because the fifty-move rule gives you plenty of room. Only bishop and knight, at up to thirty-three moves, comes anywhere near that limit.

How to checkmate in chess

Here is checkmate in one move. White plays 1.Ra8, and the black king on g8 has nowhere left to be.

1.Ra8 is mate. The rook covers the whole eighth rank, and f7, g7 and h7 are Black's own pawns.

Nothing clever happened. That is the back rank mate, the one that ends more club games than any brilliancy ever will, and it shows what mate actually is. A check with no answer.

Three things have to be true at the same time

The king is attacked. Every square it could step to is covered or occupied. And no piece of its own can block the line or capture the attacker. All three at once, in the same position. Take one of them away and you have given check, which is often useful and is never the end of anything.

Watch the mate above fall apart when Black has spent one earlier move on h6:

The h-pawn stands on h6, so after 1.Ra8+ the king strolls to h7. A check, and nothing more.

One pawn step. Players call that escape square luft, from the German for air, and pushing h6 or g6 at a quiet moment is the cheapest insurance in chess. I remind my students about it every single week and they still forget.

Now the third ingredient. Same picture, but Black has a bishop on b7:

A bishop on b7 covers a8, so 1.Ra8+ is check and Bxa8 answers it. The attacker comes straight off the board.

The check was real that time. The mate was not, because a defender covered the square the rook needed. So before you play a check, run the three questions in order. Can he move? Can he block? Can he take? Three noes and you have mated him. One yes and you have merely made him think.

Two small points that trip people up. Mate ends the game where it stands, so the king is never lifted off the board and no capture is ever made. And you do not have to say anything out loud: the move is simply written with a hash after it, Ra8 followed by #, which is what the hash mark means in a game score.

Some armies can force mate, some cannot

Once the defender is down to a bare king, the pieces left on your side decide the whole thing, and the list is short enough to memorise tonight.

A queen mates. A rook mates. Two rooks mate, and faster than either. Two bishops mate. A bishop and a knight together mate, with a method that takes an afternoon to learn and a lifetime to trust. A pawn mates too, though almost always by becoming a queen or a rook first.

Then the ones that never work. King and knight against a lone king cannot reach mate by any series of legal moves at all, so the game is drawn the moment the position appears. King and bishop, the same. Two knights are the odd case: the mating picture genuinely exists on the board, but a defender who knows what he is doing walks into stalemate instead, so it cannot be forced.

That is why chess piece values stop being the point in an endgame. Three pawns are worth more than a knight when the knight can never deliver the last blow.

The five mates worth learning, in this order

King and queen against king. Ten moves at most. Shrink the box with the queen a knight’s move away, walk your king up, mate on the edge.
King and rook against king. Sixteen at most. The same box, a slower piece, and the kings face each other.
Two rooks, the ladder. The easiest of all of them, and your king can stay in bed.
Two bishops. Nineteen at most, and the bishops work as a pair or not at all.
Bishop and knight. Up to thirty-three moves, into a corner of one particular colour. Leave it until the first four are automatic.

Every one of them ends with your king doing a share of the work, which surprises beginners. The king cannot give check, but it takes squares away better than any other piece, and there is a page on what the king can and cannot do in a mate.

Finding mate when it is your move

Two habits, both cheap.

Look at every check you have, in every position, before you look at anything else. Most missed mates are checks the player never considered because the move looked mad. Give the check in your head, then ask the three questions.

And train the pictures. Mate patterns repeat: the back rank, the smothered mate with a knight on f7, the queen next to the king with a pawn or a king behind her. Fifty mate in one puzzles will teach your eye more than an hour of reading, and the same eye then finds them two moves out. If you want a longer route into that, chess tactics for beginners walks through the patterns one by one.

Then set up a rook, two kings and nothing else, and mate a friend from the middle of the board. Until you can do that without thinking, everything else is decoration.