Digidesign does not qualify any one style of file back up.* CD-R, DVD-RAM, and Tape Backup are just a few of the options.- CD-R's are probably the most common method, however they will only store approximately 650-700mb. Some are re-recordable.- DVD-RAM's can hold up to 5.2 gigs and are re-recordable.- Tape Backup systems (various types) are capable of storing 40+ gigs and are re-recordable.- You should never back up your audio in "Compression" mode. Use a "Native" mode.- Any system that can backup/restore SDII or other compatible files will work.- Check with manufacturers regarding their systems for capacity and other specifications.