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FEN (Forsyth Edwards Notation)

It's been a long time since I had this in mind and also been a long time since I've been silent and confused for all the questions asked about FEN. So I decided the next time I encounter a question about it, I'll just share the link to this forum and remain silent XD.

FEN allows us to record where the chess pieces are on the board very quickly.

For example:
FEN: 4kb1r/p4ppp/4q3/8/8/1B6/PPP2PPP/2KR4

When the above FEN is converted into a normal position:

White: a2,b2,c2,f2,g2,h2,Bb3,Rd1,Kc1
Black: a7,f7,g7,h7,Bf8,Rh8,Qe6,Ke8

https://imgur.com/quV5XXE

But even though we see the position and check out the FEN, it is very hard to compare and understand the pattern.
Here are a few tips that might help:
1. FEN is read with respect to ranks.
2. The position is recorded rank by rank starting with the eighth rank (a8) and the ranks are separated by a "/".
3. The number in the FEN depicts the number of empty squares in the rank.
4. As we know Q is queen, K is king, N is knight, B is bishop, R is rook, P is pawn, here in FEN we use the same except that the small letters are for black and capital letters are white pieces. So q is the Black Queen and Q is the White Queen.

Thus if the whole rank contains empty squares, it is recorded as 8/
r1Bq1Rk1/ means on a8 there is a Black Rook, then an empty square (b8), a White Bishop (c8), a Black Queen (d8), an empty square (e8), a White Rook, (f8), a Black King (g8) and an empty square (h8).
Hmm.

I thought about this for a moment.

1. FEN has been computerized since Chessmaster 3000, that I know of.

2. There is really no need for FEN in real life. Games are recorded by moves. If a position show up at a move, we just go to that move.
#5
PGN is for a whole game
FEN is for a position
#7
Yes, we use PGN for the whole game. The one disadvantage about FEN is we cannot refer to each move made on board. Maybe once the move is made FEN can be used to give the position before the move and the position after the move. Hence by setting up both the initial and final position using FEN, we can find out the difference and find out the move made accordingly. This process takes a lot of time and also the same is repeated after every move.
PGN has one disadvantage compared to FEN. It can only show positions from legal games.

With FEN, you can create impossible and custom positions without regard to the game that came before it (if there was any game at all). This allows all kinds of puzzles, board start states for analysis, etc.

FEN can't show games without a whole list of FEN's (that's PGN's job). PGN can't reach illegal or custom positions (that's FEN's job).

Both PGN and FEN have their place in the world of chess.

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