For the rules of the game and definitions of the most common terms see the useful notes.
Chess is a Turn-Based Strategy tabletop board game, and is one of the most influential games in history. It is Older Than Feudalism at the very least; it has more scholarship and study devoted to it than any other game, with only Go coming close; it contains more possible directions for match to go than there are atoms in the entire universe; and it has a play named after it.
The game of chess originated in ancient India, likely in the 6th Century, possibly as a teaching tool for educating royalty in the practice of leading an army. Its exact origins are Shrouded in Myth; at least one legend attributes the very first game of chess as a reenactment of an actual battle. Whatever its exact origins, the game quickly spread westward into Persia, and then to the Islamic Middle East, with several changes made to the rules along the way. From there, the game spread further west to Europe. The game as it exists now came into being in the 15th Century, when it was overhauled to increase the maneuverability of the pieces and reduce the amount of time it took to play a single game. The most notable changes were the Queen changing from being able only move one square at a time diagonally to being the strongest piece on the board, Pawns being able to move two squares on their first move, and Bishops now being able to move any number of squares diagonally rather than being limited to exactly two (a debilitating limitation which restricted it to only 8 squares on the whole board, even if it leaped over an intervening piece of either colour).
The analytical and strategic nature of chess has led to the popular assumption that being good at chess is a sign of unusual intelligence. The Chessmaster gets his name from his ability to manipulate people and events as if they were pieces on a chessboard as well as his ability to "think three moves ahead." Shows with a rather cerebral and complex plot may employ Chess Motifs to abstract the details of the unfolding story. Finally, it just so happens to be the preferred game of The Grim Reaper (except in the Discworld, where he can never remember how the little horse-shaped pieces move).
There is a great deal of scholarship on how to play chess, including ideas on the best way to respond to to a kingside pawn, a rook, the Nimzo-Indian Defense, or an opponent who's just had a cheeseburger. Without boring you, there are several basic ways to figure out who's winning at any given moment. The player with the material advantage has, simply, more or better pieces ("material") to his name. The player with the positional advantage has more control of the board. The player with better development has more pieces in position to strike or defend, an important consideration when your stronger pieces start way back at home row and (even worse) have their movement options limited by your own pawns. And the player with "initiative" is the one trying to win, while the other is trying to not lose—he's struggling to keep up and avoid becoming their opponent's Unwitting Pawn. (Or make their opponent into one...)
Here's where the real insanity comes up: advantage in one area can make up for disadvantage in the others. Worse, in some cases, having any of these advantages can actually be a disadvantage: there are situations in which you lose because you have an extra pawn, or because it's your turn. So you gotta pick and choose — especially since it's difficult to have an advantage in all these areas at once (unless you're way better than your opponent). That said, chess has an Unstable Equilibrium and once a side gets too far behind, they can only hope their opponent blunders the game away. Accordingly, experts frequently resign before an inevitable checkmate.
Chess gives us the oft-misunderstood word "gambit". In chess parlance, a "gambit" is an opening strategy in which material is offered in exchange for positional advantage. While all strategy is about taking risks, a gambit has nothing to do etymologically with something being a gamble. It's actually derived from an Italian wrestling term, dare il gambetto, which describes a type of leg tripping motion. A gambit is a strategy which exchanges a disadvantage of one type in exchange for an advantage of a different type — and not a bet, wager, or crazy stunt with a Million-to-One Chance of success. In games that start out as a Mirror Match, a gambit instantly makes the situation highly asymmetrical, but it remains unclear which player's advantage will ultimately prove stronger. If a plan gains a clear overall advantage for one player over the other, that's not a gambit, it's just a mistake on the part of the losing player and/or superior play from the winner.
There are, of course, many other tactics. Others include forks (where one piece, often a knight, attacks two pieces or more without being attacked himself, so if you save one, you lose the other)* , pins (when a piece cannot move, as if it did, a better piece behind it would be captured* ), skewers (a variation of a pin where a valuable piece is attacked and forced to move out of the way, leaving room for an attack at a less valuable piece behind it) and sacrifices (gambits Up to Eleven in where a strong piece, even the Queen, is given away for a decisive advantage, usually for an attack against the enemy King), which generally take advantage of overloading and interference among the opponent's pieces. Chess strategy has a language all of its own.
Though the modern game has long been dominated by players from the former USSR, and there are still many strong players from Russia, there is (as of 2014) a wide variety of nationalities among the world's top players. At present, the current World Champion is Norwegian Grandmaster Sven Magnus Carlsen, who also has the highest Elo rating in history. But note that 2005 was the last year any human was able to beat the best chess-playing computer in the world.
The game provides examples of:
- Attack! Attack! Attack!: While gambits in general lead to sharp attacking lines, the Danish Gambit, Halloween Gambit and Fried Liver Attack exemplify this trope as they usually leave white's position hopeless if the attack fails. Then there is the habit of lower rank players to play pointless checks even while leaving their own king exposed.
- Attack Pattern Alpha: There are a (relatively) limited number of ways to start the game and still have a chance of winning. Chess openings are one of the most studied aspect of the game and different ones have been named, so if the white opens with the Queens Gambit, the black might respond with Slav Defence which could lead to Exchange Variation etc. etc
- Awesome Moment of Crowning: Pawn promotion, usually to a queen, usually decisive in a game.
- Batman Gambit: Obviously happens all the time in Chess as both sides try to bait each other into playing a bad move. A swindle is basically when a player pulls off such a gambit from a losing position.
- Bolivian Army Ending: Unless it's a draw, the game ends this way. The king has no way to escape, but you'll never see him getting captured.
- Boring, but Practical: Pawns. Not as fun as the other pieces, but pawn positioning is very important, to the point that whole schools of strategy have been made on optimal use of pawns to control the board. As individual pieces they cost very little material-wise for being able to deny (usually) two squares and are often important for protecting other pieces.
- Calling Your Attacks:
- The rule commonly followed at the amateur level is that the player who places their opponent in check must announce "check" as they make the move. In tournament play, this isn't a rule though.
- In "Memory Chess", where one or both players must play by the board they can imagine in their heads, calling out or writing down what piece goes where is the only way to play.
- Character Death: Any piece that gets captured stays off the board for the rest of the game.
- Epic Fail: Losing to Fool's Mate or Scholar's Mate where you're checkmated in two to four turns. Also, even high level chess players are not immune to game-losing blunders
- Even the Subtitler Is Stumped: In chess annotation, ! and ? symbols mark good and bad moves, with ?! specifically meaning "dubious but not completely bad." However, !? has the general meaning of "interesting," which usually means that the annotator can't figure out whether it's good or bad, but it is interesting. One grandmaster joked that it's the mark of a lazy annotator who doesn't want to work out whether the move was good or bad. (It's also sometimes used for Crazy Enough to Work plans in a losing game, which is not quite this trope.)
- Field Promotion: Pawn promotion; a pawn that reaches the opposite side of the board is promoted to any (non-King) piece of the player's choosing. Naturally, most players take advantage of promoting to Queen. Anything else is designated "underpromotion".
- From Nobody to Nightmare: The pawns in potential. See at Field Promotion.
- God Save Us from the Queen!: God save us from the enemy's queen, the most powerful and dangerous piece on the board. Taking her head on is usually a death sentence for any piece foolish enough to try.
- Golden Snitch: Some variants do this. Three check chess has the additional win condition that the first player to get three checks in wins. King of the Hill chess has the additional win condition that the first player to get his king onto one of the four center squares wins.
- Guide Dang It!: While most people can tell you the general rules, some rules only have impact in late-game play and are therefore rare enough to encounter that people tend to forget how exactly they work.
- The En Passant maneuver ("in passing"), where a player with a pawn in position to capture an enemy pawn if it moves forward one space, and the opponent moves it two spaces forward to evade the capture, the offensive player may move his pawn as if to interrupt the defending pawn "in passing". This rule can only be taken advantage of immediately after the defending pawn moves forward.
- The "threefold repetition" rule - that either player may declare a game drawn if the same position occurs for the third time - is a particularly egregious example. The rule refers to a position, rather than a move, repeated three times. At this point, a draw may be taken (this normally happens when moves are repeated but doesn't have to). There have been a few high-level cases where a player has unintentionally let this happen.
- If 50 moves are played without a pawn move or a capture the game is drawn. It was thought when this rule was added to tournaments that all such positions must truly be drawn, but computer analysis has shown that there are indeed a few positions that are forced mates requiring more than fifty moves, however the rule remains in place (in part because some of the discovered positions require hundreds of moves to reach checkmate).
- Instant-Win Condition: If either King is put in a position of certain doom, the game ends, even if that King's team failed to lose a single piece the entire game.
- Irrevocable Order: The touch-move rule. Once you pick up a piece with the intention of moving it, you have to move it. If your move is illegal, you have to take it back but still have to make another with that same piece if possible. However, by first saying "I adjust" (or "J'adoube" in French), you can touch a piece on your turn to adjust it (move it closer to the center of the square) without having to move it.
- Mechanically Unusual Fighter: The knight moves along lines none of the other pieces use, allowing it to move between them, but allowing them to attack it without being in danger from it.
- Metagame: Chess has a metagame, evolved over eons of play. One might say that the metagame is the game. If you have ever played in any organizationally-sanctioned tournament, held anywhere at all, at some point in your life, it is guaranteed that every move you made was dutifully logged via algebraic notation* , and then almost certainly dissected down to numbingly exhaustive detail, so as to understand every available nuance of both how you played then, and potentially will now.
Gary Kasparov's famous rematch versus Deep Blue in 1997 involved a curious metagame factor. In the first game, Deep Blue made a puzzling play that was really just a hole in its heuristics - it is only as good as its program. This threw Kasparov for a loop. In the second game, Deep Blue made a second error, which Kasparov did not see and cost him the game. Some of the reports basically amounted to Gary being unable to believe the machine could screw up so badly. He attributed the moves to deep insight and thought himself out of a draw, turning it to a loss.
- The Millstone:
- The famous Smothered Mate (see illustration) where a single knight attacks a king surrounded by its own "protective" pieces who block out all escape squares, allowing this beautiful (and somewhat embarrassing) checkmate.
- "Back Rank" checkmates where the King is checked by the opponent's Rook or Queen, and its forward escape squares are all blocked by its own pawns or pieces.
- This is also part of why beginning players tend to be cavalier about discarding their pawns: why waste a turn on them when you could be using it to deploy your more powerful pieces? Oh, right: because they're in the way. In this case, it's a subversion; pawns are vitally important to your position, and trying to "get them out of the way" is a mark of a rookie.
- Mook Promotion: Pawns, if they get across the board, can become queens, bishops, rooks, or knights.
- Never Say "Die"/Nobody Can Die: Despite chess being meant to resemble a battle, pieces removed from the board are always "captured", never "killed". The king can't even be captured (where he would that's checkmate). May make sense if it's understood as the pieces are only removed until the game is over, and then they play all over again...
- Obvious Rule Patch:
- The "same rank" rule of castling (curing a Good Bad Bug).
- Also, the 50 move ruleExplanation , which at one point, was itself patched, patched again, and then finally unpatched.
- You used to be allowed to promote a pawn to one of the other player's pieces* or leave it as a Pawn* . You could also move into triple check (only check and double check counted as check) and checkmate with an illegal move.
- En passant is a patch on the two-square initial pawn move, which was created because the early game was so slow.
- Chess tournaments enacted the "no talking" and "touch-move" (no taking back moves) rules because of players distracting each other or outright screwing with each other, such as making moves then immediately taking them back several times in a row. Further sportsmanship rules were added to deal with non-verbal means of getting under an opponent's skin.
- One-Hit-Point Wonder: Any piece can capture (or, in the case of the King, check or mate) any other piece with a single attack. Rank doesn't matter; a pawn can capture a queen just as readily as a queen can capture a pawn.
- Press Start to Game Over: The fool's mate, which puts White into a checkmate in two moves.
- Sadistic Choice:
- Forks (where one piece threatens two pieces) and skewers (where a valuable piece is threatened, but moving it would expose another piece to attack) are this; you're going to lose something unless you Take a Third Option.
- Zugzwang is a situation where any move by the player to move will weaken his position - but of course, he has to move.
- Straight for the Commander: Because both sides are a Keystone Army, your only win condition is to take out the enemy king. Taking out other enemy pieces doesn't directly matter, although it makes life easier for you.
- Stupidity Is the Only Option: Zugzwang (German for "compelled to move") occurs when any move you make will weaken your position, yet you must make a move because passing your turn is not allowed.
- Surprise Checkmate: It's technically possible to get your own king out of danger and completely trap the opposing king, but this is very rare. It usually requires your opponent to not be paying attention, or is running so low on time that they can't really afford to think about strategy.
- Switch-Out Move: The King and one of their Rooks may exchange places* one time during the game (this is the only time a King can move more than one square).
- Timed Mission: Most organized competitions give each player only a certain amount of time to make all of their moves. If a player's time runs out, that player automatically loses.
- Took a Level in Badass: The pawns, when promoted by getting to the opposite side of the board, are exchanged for any other piece (except for a second King).
- Updated Re-release: The "New Chess" rules adopted in the 15th century and currently in use.
- We Cannot Go On Without You: From each player's perspective, if their own King is ever placed in checkmate, the game ends.
- We Win... Because You Didn't: It's often possible to force your opponent to draw from a losing position. High level chess tournaments are won by score or just "best out of X games", which encourages players to try for a draw if they're losing
- Whammy: There is a non-luck-based version, the form of zugzwang called the trebuchet.
- Zerg Rush: Dunsany Chess or "Horde Chess" is a variant featuring a standard chess army against 32 pawns.
Fictional works about chess:
- Dangerous Moves, a thriller about a world chess championship competition
- Knight Moves, in which a grandmaster has to juggle playing for the world championship and catching a Serial Killer at the same time
- Pawn Sacrifice, a Bobby Fischer biopic
- Queen of Katwe, about a chess prodigy living in dire poverty in South Africa
- Searching for Bobby Fischer, about a chess prodigy trying to balance the game and real life
- SCP Foundation's SCP-1875. It's a chess AI with a magnetic chess board that can move the AI's pieces. It has a dial with multiple levels of AI difficulty, with the final setting causing the AI to make illegal moves and bad moves and become violent with the pieces. As for the parts of the AI and chessboard that don't directly involve the game, things get...very creepy, as per SCP standards.