6.00 DOS Operating System Microsoft MS-DOS 6.00 (1.2M Disk 1) MS-DOS 6.00 (1.2M Disk 2) MS-DOS 6.00 (1.2M Disk 3) MS-DOS 6.00 (1.2M Disk 4) MS-DOS 6.00 (1.44M Disk 1) MS-DOS 6.00 (1.44M Disk 2) MS-DOS 6.00 (1.44M Disk 3)