Yeppers - DMS was used to pack an entire floppy disk into a single compressed file (like Lha compresses a bunch of files into a single archive).
If you need to get a DMS back to a floppy, but have no Amiga floppy drive (for whatever reason) - do a search on Aminet for FMS or a similar virtual floppy system - you can unpack and mount it that way.
Siggy.