FORSYTH-EDWARDS NOTATION
The Scottish journalist and
chess player, David Forsyth (1854-1909), created a simple system for describing
chess positions. It was later extended by Steven J Edwards so that computers
could use the notation to store more detailed information about a position.
Forsyth's system
Examples of common positions
DESCRIPTION |
FORSYTH
NOTATION |
Starting
position |
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR |
Italian
game |
r1bqk1nr/pppp1ppp/2n5/2b1p3/2B1P3/5N2/PPPP1PPP/RNBQK2R |
Mate for
Black |
8/8/8/8/8/6k1/8/3q3K |
Stalemate |
1k6/1P6/1K6/8/8/8/8/8 |
Edwards adaptations
Braille books and websites
describing positions will often only use the notation as described above. The
rest of the notation gives more specific information about the game and is
normally used by computers.
There are six fields used in the
full notation, each separated by a space.
1. Position
The previous section outlines
how this works.
2. Player to move
A lower case "w" means
White to move and a lower case "b" means Black to move.
3. Castling rights
A single hyphen means that
neither player can castle. If this is not the case, a combination of four
letters shows what castling rights both players have. The letters K and Q are
used to show whether king-side or queen-side castling is possible. As with the
position notation, upper case means white and lower case means black. Examples:
- |
Neither
side can castle |
KQkq |
All
castling is possible |
Kk |
Both
sides can only castle short |
kq |
Black can
castle either way |
Qk |
White can
castle long and Black short |
4. En passant square
This field is used to show if a
pawn has just moved forward two squares. If no such move has been made it shows
a hyphen, otherwise it will show the square behind the pawn where a pawn would
land if capturing en passant.
5. Half move clock
This number increases by one
each time either player moves until a pawn is moved or a piece is captured at
which point it is set to zero. It is used to determine if a 50
move draw can be claimed.
6. Move number
This shows the move number as
written down in a score sheet. The first move of the game for both white and
black is 1, the second is 2, the third is 3, and so on.