FBX alias Filmbox is a patended file format (.fbx) that is developed by Kaydara and acquired by Autodesk since 2006. It is mainly applied to offer interoperability among digital content creation applications. FBX is also part of Autodesk Gameware, a series of video game middleware.
It is also possible to open FBX files in blender. Go to File->Import and select the BOS FBX importer. Navigate to the FBX file that should be imported, choose it, and click to start the import. The model and armature will be imported.