Disk the Masher system (.dms) was an often used method on Amiga, to create a compressed image of a discs (typically floppy). The discs were read block-by-block, and their data structure was maintained. The DMS won approval particularly in the demo scene and the Warez scene, since with this system disc images could typically be distributed easily in mailbox networks like FidoNet or via telecommunications (modems).

The DiskMasher format is copyright-protected and has problems storing specific sequences of bits due to bugs in the compression algorithm, but was widely used in the pirate and demo scenes.