Fbx

.FBX (Filmbox) files are a proprietary but widely used 3D graphics, animation, and motion capture format originally developed by Kaydara and released in 1996. Kaydara was acquired by Alias in 2004, and Alias was itself acquired by Autodesk in 2006, which now owns the FBX format. Various 3D graphics and animation programs contain FBX import and export scripts, including the free and open-source Blender. Banished uses .FBX files for all 3D models including buildings and animals.

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Wikipedia