IBM Extended Density Format

The IBM eXtended Density Format (XDF) is a way of superformatting standard high-density 3½-inch and 5{¼-inch floppy disks to larger-than-standard capacities. It is supported natively by IBM's PC DOS versions 7 onward and by OS/2 Warp 3 onward, using the XDF and XDFCOPY commands (directly in OS/2).