XBoard, also known as WinBoard on Microsoft operating systems, is a free graphical user interface client developed by Tim Mann that is compatible with various chess engines that support the Xboard Communication Protocol such as GNU Chess.
Arena is a free Graphical User Interface (GUI) for chess. Arena helps you in analyzing and playing games as well as in testing chess engines. It runs on Linux or Windows. Arena is compatible to UCI and Winboard protocols.
Tarrasch is a flexible, minimalist, and easy to use chess GUI. It is ideal for playing against and training with chess engines. Tarrasch has a built in engine but can just as easily be used with other UCI engines such as Rybka or Houdini.
Raptor is a cross platform chess interface and pgn viewer for the free internet chess server: FICS. It has the following features:
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