Validating and writing system software to the filesystem

FFS was designed as a full replacement for the original Amiga filesystem.FFS differs from its predecessor mainly in the removal of redundant information.

Kickstart 1.3 provided autobooting support so that the machine could now be booted from hard disk or reset-proof RAM disk ("RAD:"), whereas earlier Kickstart releases could only be booted from floppy disk.

Workbench 1.3 provided the FFS filesystem device driver on disk, which could be copied into the Rigid Disk Block (RDB) on hard disks.

This resembled a very simple form of filesystem journaling.

To allow the disk to be used again with an invalidated OFS or FFS filesystem, the entire disk has to be completely scanned and the bitmap rebuilt, but only the data being modified during the write would be lost.

Given these advantages, FFS was rapidly adopted as the most common filesystem used by almost all Amiga users, although OFS continued to be widely used on floppy disks from third-party software vendors.