Distribution Media Format
Distribution Media Format is a file format for floppy disks that Microsoft created to distribute software programs.
The format allowed for the disk to hold 1680 KB of data instead of the standard 1440 KB.
The standard was also a pioneer of anti-piracy, as utilities had to specifically support the format, or reading/writing could not occur.
Office 4.0 was the first software product made available using this format.