You should make a backup copy of your QuickBooks company on a daily basis. If you should lose data for any reason, you can restore data from your backup copy.
Recommended backup routine
The Backup command does not simply make a copy of your company file; it also compresses the data into a compact file that is smaller than your company file.
Note: QuickBooks doesn't support backup to floppy disks.
Your backup is saved to your MobileMe account as an encrypted .dmg file for added security. You need an active MobileMe account with available space on your iDisk and an Internet connection to use this feature.
Note: If you used QuickBooks 2007 for Mac and backed up to your .Mac account, you can use those backup files in QuickBooks 2007 for Mac only.
QuickBooks saves your backup file to your iDisk in the Documents > QuickBooks > Backup Files folder.
You can choose to automatically back up to a hard disk, to your iDisk, or both.