Useful Notes / Chess

The starting position. The letters and numbers label the board squares in algebraic notation.

This page reviews the basic rules of chess and enough terminology to discuss the tropes associated with the game.

Chess is played on a checkered board with 64 squares in an 8-by-8 arrangement. The initial setup is literally a Mirror Match; Black's set up is the reverse of White's, so that the respective Kings and Queens appear to be facing one another. (The simple mnemonic is that the Queen is fashionable and "her dress matches her shoes," meaning she should always start on a square of her own color.) Another mnemonic is that dames are set up on d squares (algebraic notation). The board is orientated so that both players have a white square at the bottom right of the board from their perspective ("white on the right")— getting this wrong indicates a complete beginner in Real Life and is a serious mistake in fiction (unless depicting complete beginners).

The Pieces and How They Move

All pieces in chess move in straight lines for one or more squares (yes, even the knight—see below). The pieces that can move more than one square cannot move through squares occupied by allied pieces and cannot move beyond the squares occupied by enemy pieces. If an enemy piece blocks a line of movement, it can be captured by removing it from the board and replacing it with the capturing piece, except for in the case of a pawn.

Rook

Set up in the corners of the board and shaped like castle towers in most sets. Originally, they represented war chariots or siege towers. They move along ordinal lines—forwards, backwards, left, and right. In the illustration, the squares the rook can move to are in green.

Bishop

Two per player. Have a top shaped like a bishop's miter. They originally represented war elephants, but such were unknown in Europe (Hannibal Barca notwithstanding) and the imagery eventually aligned to the environment. Can move any number of squares diagonally. In the diagram to the left, these squares are highlighted in green. A consequence of the bishop's move style is it can only ever see half the board; a bishop that starts on a light square will remain on light squares for the whole game. As a result, players often refer to bishops as being "light-squared" or "dark-squared".

In French, they're called fou (the fool, or jester). In German, they're Läufer and in Dutch, they're loper (both meaning runner). In Italian, Alfieri (Flag bearers). And in Russian, slon (elephant). In Finnish, lähetti (messenger/courier). Go figure. On the other hand, in Spanish, they're called "alfil" (derived from Arabic, derived in turn from old Persian "pil", meaning "elephant"). In Hebrew, they're called "ratz" (runner/messenger), similar to the German, Dutch, and Finnish versions (which is understandable, seeing as most of the early Israelis were German-born). In Croatian, they are called "lovac" (the hunter). In Romanian, they are called "nebun" (the madman) for some reason.

Queen

One per player. Usually the second-largest piece, and tends to have a small knob on its coronet-shaped top. Can move any number of squares left, right, forwards, backwards, or diagonally, thus combining the powers of rook and bishop. The queen in the illustration on the left can move to any green square.

King

The king is the heart of the player's force. If he is ever in "check," a position in which he can be captured on the next turn, his player must take action to protect their king; it is literally against the rules to leave the king in check. They must either move the king out of the line of fire, interpose another piece between king and attacker, or capture the attacker. The king is also not allowed to move into or through check.

Traditionally the tallest piece, with a cross on top. Moves like the queen, but only one square at a time. The king, along with the rook, can be moved together in a move known as castling. To castle, move the king two squares toward the rook instead of the normal one, then place the rook on the square the king skipped over. To be eligible to castle, both king and rook cannot have moved yet. Also, the king cannot be in check, cannot move through check, and cannot end in check.

Pawn

Representing infantry, each player starts with eight of these, filling the entire second row forward from each side. They move one square forward at a time, except for an optional two squares when moved for the first time.

Unlike all other pieces, a pawn does not capture the same way it moves. When capturing, a pawn moves diagonally forward one square. If a pawn moves two squares, skipping over a square that an enemy pawn could have captured it on, then on the next turn (and only on the next turn), the opponent may choose to capture it en passant. The capturing pawn moves to the square the enemy pawn passed over.

In the diagram on the left, the white pawn on e2 can capture the black pawn on d3 or move to e3. Since it hasn't moved yet this game, it can also move to e4, but if it does, the black pawn on f4 can immediately capture it en passant by moving it back to e3 and capturing it on that square.

If a pawn makes it all the way to the farthest row on the board, they're instantly upgraded into any other same-color piece of their player's choosing, apart from the king, usually a queen.

Beginning players tend to write pawns off as useless and obstructive, but players of skill know that they are one of the most critical parts of the game. Pawns' ability to become queens is not their only strength—they are highly effective defenses as well, as the other player is unlikely to sacrifice another piece to capture one except as part of a tactical sequence or attack.

Knight

Two per player, appearing as horses, which represent armored cavalry. Probably the most recognizable board game piece in the world. The knight moves to one of the closest squares not on the same rank, file, or diagonal, ignoring any pieces in the way. Its movement is highlighted in green in the illustration above.

The illustration above also compares the movement of the knight (green lines) to that of the queen (red lines). A queen moves orthogonally (north, south, east, or west) or diagonally (northeast, southeast, southwest, northwest). The knight moves along lines located between these; these lines are similar, but not identical, to half-winds on a compass rose (north-northeast, east-northeast, etc.). Since these lines do not pass through the center point of the squares adjacent to the knight, it moves to the first available square along the line.

Note that the knight is sitting on a light square, and it can move to any of the eight dark squares that lie on the ring of squares that are two squares away. A queen sitting on its square can move to the other eight squares in this ring (highlighted in red).

This special move allows the knight to threaten a queen without putting itself in danger. Indeed, a knight is never threatened by a piece it attacks and can never threaten a piece that is attacking it, except for an enemy knight.

Playing the Game

Players alternate turns, with White always having the first move. The object of the game is to check the enemy king such that he will be attacked no matter what move is played, which is known as checkmate. The game also ends with a victory if a player resigns, or gives up. Most high-level games end this way (or in a draw), as it's considered unsportsmanlike for advanced players to keep playing when they are obviously going to lose.

The game can end in a draw by:

• Stalemate: There are no legal moves for the player to move, but their king is not in check.
• Threefold/fivefold repetition: The same board position is reached three (drawn on request)/five (drawn by arbiter) times. Note that it is not enough for all pieces to occupy the same squares; all of the following must also be true:
  • The same player has the move.
  • All castling rights are identical.
  • The possibility to capture en passant is the same.
• 50/75-move rule: 50 (drawn on request)/75 (drawn by arbiter) moves occur without a capture or pawn move.
• Dead position: The game reaches a position where checkmate cannot be reached by any series of moves. This usually, but not always, occurs due to insufficient material.^note Any endgame resulting in two lone kings, a lone king against a single knight or bishop, or opposing bishops on the same color is automatically drawn by this rule.
• Draw by agreement: Players agree to a draw. This usually occurs in lifeless positions where both players consider checkmate to be unlikely, e.g. endgames with each side having a bishop on opposite-colored squares.

Chess is frequently played with a timer so that each player has a limited amount of time to make their moves. In this case, the game ends if a player runs out of time, whereupon they lose if their opponent has a possible checkmate and draw otherwise.