An image backup consists a copy of the database file and/or the transaction log, each as separate files. Image backups provide more flexibility for transaction log management than archive backups do.
You can make an image backup using the Backup utility, the Create Backup Images wizard, or the BACKUP DATABASE statement. Image backups are available on all supported platforms, and are the only supported type of backup on NetWare and Windows CE.
To make backups to tape using an image backup, you have to take each backup copy and put it on tape using a disk backup utility.
Understanding parallel database backups