3MF, 3D manufacturing format, is used by applications to render 3D object models to a variety of other applications, platforms, services and printers. It was built to avoid the limitations and issues in other 3D file formats, like STL, for working with the latest versions of 3D printers. 3MF is relatively a new file format that has been developed and published by the 3MF consortium.
FBX, FilmBox, is a popular 3D file format that was originally developed by Kaydara for MotionBuilder. It was acquired by Autodesk Inc in 2006 and is now one of the main 3D exchange formats as used by many 3D tools. FBX is available in both binary and ASCII file format. The format was established to provided interoperability between digital content creation applications.