FBX (Filmbox) is a proprietary generic 3D interchange format owned by Autodesk. It is designed to share model data between different content creation applications like Maya, 3ds Max, and MotionBuilder. Unlike OBJ, FBX supports complex data such as animations, skeletal rigs, skinning, lights, and cameras, making it a favorite in the game development and visual effects industries. Sample FBX files are used to test complex 3D asset pipelines. Developers use them to verify that skeletal animations play back correctly and that material properties are preserved during transfer. They are also used to test interoperability between various game engines (like Unity and Unreal Engine) and modeling tools.