This preset now uses the new code for identifying check, checkmate, and stalemate. Let me know of any problems with it.






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8 k
7 p p p p
6
5 r
4
3 B n P
2 P P K B P
1 R R
a b c d e f g h

Chess

White:
Black:



Orientation:
Scale:

Render as:
Shape:

Piece Set:

Colors:


a Chess problem from this position.

Rules of Chess

K
King
Q
Queen
R
Rook
B
Bishop
N
Knight
P
Pawn

The object is to checkmate the King, which happens when the King is under attack and cannot move to a safe square. The King moves one space in any direction, and cannot move to a square where he would be under attack. If a King and Rook haven't moved, all spaces between them are empty, and the King is not in check, it may move two spaces toward the Rook, with the Rook leaping to the space the King passed over. This is called castling. The King cannot castle if it would pass over any attacked squares in its move.

Other pieces are Rooks, Knights, Bishops, Queens, and Pawns. Rooks move any number of empty spaces along a straight line. Bishops move any number of spaces along a diagonal line. Knights move two spaces in a straight line, then move one more space at a right angle, jumping over any intervening spaces. The Queen moves as a Rook or Bishop. The Pawn moves one space straight forward, and captures one space diagonally forward. When the Pawn reaches the last rank, it promotes to any piece but the King. On its first move, a Pawn may move two spaces straight forward. If, in moving two spaces, a Pawn lands next to any enemy Pawn on the same rank, that Pawn may capture it on the immediately following turn by moving to the space it moved over. This is called en passant. Other than capturing by en passant, all captures are by displacement. One piece captures another by moving to its space.

Notation

You should be aware that Game Courier's notation is not identical with standard Chess notation. Game Courier has been designed for general use with any of several different Chess variants, and it accordingly uses a generic system of notation. This system is described in detail in the User's Guide. Here are the basics you need to know for Chess. Move a piece by writing its present coordinate, a hyphen, and its destination coordinate. For example, "e2-e4". There is no special operator for captures. A hyphen should be used even when a piece is captured. To signal to your opponent what piece you moved, and to provide an extra bit of error checking on the move you enter, you may include Game Courier's notation for the piece before the move. For example, "P e2-e4". Note that Game Courier uses uppercase letters for White pieces and lowercase for Black pieces. Black could enter "p e7-e5" for a move but not "P e7-e5".

Most moves must be written explicitly. Game Courier does not rely on context to understand ambiguously written moves, such as "e4", which makes sense only when one piece can move there. Promotion should be handled by explicitly adding the promoted piece to the space the Pawn has moved to. For example, "P f7-f8; Q-f8" would move a White Pawn from f7 to f8 and promote it to a White Queen. Because this preset is automated to enforce rules and handle special moves, it allows slightly abbreviated expressions for en passant and castling. En passant should be entered as a move by your Pawn. For example, "P e5-f4" would capture by en passant a Black Pawn that had just made a double move to f5. When receiving a move like this, this preset will check whether it is a legal en passant move, and if it is, it will automatically capture the enemy Pawn. Castling should be entered as a move by your King. Just move your King where it would go in the castling move. The preset will then check whether castling to that space is legal, and if it is, it will automatically move the Rook to the space the King passed over.

How to Move Pieces

Full Algebraic Notation

Algebraic notation identifies each space by a coordinate that begins with its file label and ends with its rank label. On the Chess board, files go up and down from one player to the other, and ranks go from left to right. In most games, files are represented by letters, and ranks are represented by numbers, but there is no fixed rule requiring this for all games, and some games, such as Shogi, reverse this convention. If you look at the diagram, you will usually see the file labels going from left to right and the file labels going up and down. And if you hover your mouse over a space, you will normally see the name of the coordinate appear in a tooltip.

It is not uncommon to see algebraic notation being used for Chess, but it is often in an abbreviated format that requires you to know both the rules of the game and the current position to know exactly which piece moves where. For example, the notation "Ne6" indicates that a Knight is moving to e6, but it doesn't indicate which Knight, and it doesn't specify where the Knight is coming from. To figure this out, you need to know how a Knight moves and which Knight on the board can make a legal move to e6.

Although rules may be programmed for individual games, Game Courier itself does not know the rules of any game, and it is unable to parse abbreviated algebraic notation. Therefore, it relies on full algebraic notation, which completely specifies the move without requiring any knowledge of the game's rules or the current position. The most usual type of full algebraic notation indicates the piece that is moving by its label, the space it is moving from, and the space it moving to. In Chess, a typical first move might be written as "P e2-e4". When you hover your mouse over a piece, you will normally see the piece label followed by the coordinate for the space, and when you hover it over an empty space, you will normally see the coordinate label. Including the piece label in your notation allows Game Courier to check that the piece you're moving is the right one, and it makes game notation easier to follow, but it is not mandatory.

You may promote a piece by including a promotion move after your regular move. A promotion move has a piece go directly to a coordinate. Here is an example: "p e7-e8; q-e8".

You may remove a piece from a space by adding an @ to the space or by omitting the destination coordinate. For example, both "@-e4" and "e4-" would remove the piece on "e4". This is useful for en passant when you are playing a game that does not handle this automatically. For example, "P d5-e6; e5-" removes the Pawn on e5 after a Pawn moves from d5 to e6.

You will not need to remove spaces for most games, but if you should need to, you can do this by omitting the first coordinate in a move. For example, "-e4" would remove e4 from the board. To add or return a space to the board, you may add an @ or any other piece to it.

Available Pieces

Pieces are represented by labels, usually using uppercase letters for White and lowercase letter for Black. When you enter a move or specify the starting position for a game, you should remember that piece labels are case-sensitive. Many piece sets are available for use with Game Courier, and this table shows you which pieces belong to the piece set you are currently using.

These pieces come from a set containing more pieces, but this preset has had the set of pieces reduced to those used in the game.

WBishop.gif
B
WKing.gif
K
WKnight.gif
N
WPawn.gif
P
WQueen.gif
Q
WRook.gif
R
BBishop.gif
b
BKing.gif
k
BKnight.gif
n
BPawn.gif
p
BQueen.gif
q
BRook.gif
r

Credits

This preset uses the JPG-Alfaerie settings file for Chess, which was made by Fergus Duniho.

Game Courier was created, programmed and written by Fergus Duniho.

Game Courier, Copyright © Fergus Duniho, 2001-2017


WWW Page Created: 15 August 2001

Kibbitzing Etiquette

Kibbitzing is the practice of commenting on a game you are not playing. In commenting on a game, please follow these rules of etiquette.

(1) If you notice that someone has made an illegal move, please mention it. Some Game Courier presets cannot enforce rules, but Game Courier does enable players to take back any previous move. Details on how to take back a move are provided in the User's Guide, linked to above the board.

(2) Unless otherwise specifically asked to, do not offer hints or suggestions to players on what moves they should make. In general, avoid coaching comments.

(3) Once a game is over, it should be alright to offer your analysis of the game and your specific comments on what moves players should have made. If some players don't want this, they may mention it in the Kibbitzing section, and you should honor this request by not commenting on the game.

(4) Be polite. At the appropriate time, offer any criticism you have in a constructive manner. Avoid heckling players for bad moves.

(5) Don't spam this space with irrelevant comments. If you have a comment about Game Courier, rather than about the specific game you're viewing, please post it on Game Courier's Index page to give it.