fen

A FEN (Forsyth-Edwards Notation) is a way to represent a chess board's position using a simple text string. It encodes the placement of all pieces, whose turn it is to move, castling rights, en passant targets, and move counters in a standardized format. This helps computers and players quickly share or analyze specific positions without needing visual diagrams. Think of it as a compact, code-like snapshot of a chess game at a particular moment.