File Allocation Table or FAT is a computer file system architecture originally eveloped by Bill Gates and Marc McDonald in 1976/1977. It is the primary file system for various operating systems including DR-DOS, OpenDOS, freeDOS, MS-DOS, OS/2(v1.1), and Microsoft Windows (up to Windows Me). For floppy disks (FAT12 and FAT16 without long filename support) has been standardized as ECMA-107 and ISO/IEC 9293. The use of long filenames with FAT is patented in part.