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.
A file with .usdz is a ZIP archive for the USD (Universal scene description) file format that contains and proxies for files of other formats embedded within the archive.