 Partition IDs are not used to specify a type of file system by themselves.The original FAT file system (or "FAT structure", as it was called initially) was designed and coded by Marc McDonald, based on a series of discussions between McDonald and Bill Gates.It was introduced with 8-bit table elements (and valid data cluster numbers up to 0xBF) in a precursor to Microsoft's "Standalone Disk BASIC-80" for an 8080-based successor of the NCR 7200 model VI data-entry terminal, equipped with 8-inch (200 mm) floppy disks, in 1977 or 1978.