Web site: stockfishchess.org
Category: Games
Sub-Category: Board
Platform: Linux, OS X, Windows, iOS, Android
License: GNU GPL
Interface: GUI
Wikipedia:
First release: 2008
Stockfish – a free, open-source, and powerful UCI chess engine derived from Glaurung 2.1. Stockfish is not a complete chess program and requires a UCI-compatible graphical user interface (GUI) (e.g. XBoard with PolyGlot, Scid, Cute Chess, eboard, Arena, Sigma Chess, Shredder, Chess Partner or Fritz) in order to be used comfortably. Read the documentation for your GUI of choice for information about how to use Stockfish with it.
The Stockfish engine features two evaluation functions for chess, the classical evaluation based on handcrafted terms, and the NNUE evaluation based on efficiently updatable neural networks. The classical evaluation runs efficiently on almost all CPU architectures, while the NNUE evaluation benefits from the vector intrinsics available on most CPUs (sse2, avx2, neon, or similar).
The Stockfish project started with the open source Glaurung engine, authored by Tord Romstad. In November 2008, Marco Costalba forked the Glaurung 2.1 code and introduced Stockfish 1.0. Tord and Joona Kiiski joined the Stockfish project and the Glaurung project slowly faded away. Meanwhile, Stockfish quickly rose to become the strongest open source chess engine, with frequent updates every few months. Today, it remains one of the strongest engines in the world.