Max Disk Formatter is a utility program used to format floppy disks, and was often used to format them to nonstandard (larger) sizes. Disks formatted by MDF cannot be used in a conventional manner, even with the standard format size, because of the non-standard file system.
As floppy disks are now not widely used. This program is now obsolete. However, it has one feature that is useful for old computers: it can format diskettes which are not able to be formatted by the standard DOS format program.