Chessचेस

The board and the pieces

Chess is played by two players on a board of 64 squares, eight by eight, with a light square in each player's right-hand corner. Each player has sixteen pieces: a king, a queen, two rooks, two bishops, two knights and eight pawns. One side is White, the other Black, and White always moves first.

When you set up a table you choose whether player 1 plays White, Black, or a colour picked at random.

How the pieces move

• King: one square in any direction.
• Queen: any number of squares along a row, a column or a diagonal.
• Rook: any number of squares along a row or a column.
• Bishop: any number of squares along a diagonal, so it stays on one colour all game.
• Knight: in an L shape, two squares one way and one square to the side. It is the only piece that jumps over others.
• Pawn: one square straight forward, or two from its starting square. It captures one square diagonally forward, never straight ahead.

Pieces other than the knight cannot pass through other pieces. You capture by moving onto a square held by an enemy piece, which leaves the board. You can never capture your own pieces.

Check and checkmate

A king that is attacked is in check. You must answer a check at once: move the king, capture the attacker, or block the line between them. You may never make a move that leaves your own king in check.

If a king is in check and there is no move that saves it, that is checkmate and the game is over. The player who gave checkmate wins. The king is never actually captured.

Special moves

Castling: once per game, the king moves two squares towards one of its rooks and that rook hops over to the square beside it. To castle, tap the king and then the square two steps away. You may castle only if neither the king nor that rook has moved yet, the squares between them are empty, the king is not in check, and the king does not pass through or land on a square that is attacked.

En passant: when a pawn moves two squares forward and lands beside an enemy pawn, that enemy pawn may capture it as if it had moved only one square. It must do so straight away, on the very next move, or the chance is gone.

Promotion: a pawn that reaches the far side of the board becomes a queen, rook, bishop or knight of the same colour, whichever you choose. Nearly everyone picks a queen, but a knight sometimes gives a checkmate the queen cannot.

How a game can be drawn

Not every game has a winner. This table ends the game as a draw automatically when:

• Stalemate: the player to move is not in check but has no legal move.
• Threefold repetition: the same position, with the same player to move, has come up three times.
• The fifty-move rule: fifty moves by each player have gone by without a capture or a pawn move.
• Not enough pieces: neither side has enough left to give checkmate, for example king against king, or king and bishop against king.

You can also agree a draw. On your turn, offer a draw before you move; the offer stays open while your opponent thinks. They can accept it, decline it, or simply move, which declines it. After an offer you have to wait five of your own moves before you can offer again.

Resigning

If you can see that the game is lost, you may resign on your turn. Your opponent wins at once.

Choosing colours

Player 1 can play White, Black or a colour picked at random. White moves first, which is a small advantage, so swapping colours between games keeps things fair.

The computer

Easy plays like a beginner of about 800 rating: it looks one move ahead and often misses what you are planning. Normal plays like a club newcomer of about 1200: it looks two moves ahead and rarely gives pieces away. Hard searches for up to about 0.4 seconds a move and plays strong, steady chess. All three know some popular openings.

Rules this table does not use

There are no clocks, so there is no losing on time; the table's turn timer, when it is on, plays a quick sensible move for you instead. Repetition and the fifty-move rule end the game automatically rather than needing a claim.