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Engine terms, explained

Short answers to the words you meet in an engine response, each with a position you can run against the API.

• CentipawnThe unit of a chess evaluation: 100 centipawns is one pawn of advantage.
• Search depthHow many plies ahead the engine has fully searched; cost grows about 1.6× per ply.
• NNUEThe neural network Stockfish uses to evaluate positions since 2020.
• MultiPVAsking the engine for the best N lines instead of one.
• Win / draw / lossThe engine's probability estimate for each result, per mille.
• FENThe one-line text format for a chess position.
• UCIThe text protocol chess GUIs use to talk to engines.
• Limited strengthMaking Stockfish play at a chosen rating.