Complex sentence: Backup can be used in connection with either a user's online MobileMe iDisk or the Macintosh's CD-RW or DVD-R drive to make safe, archival copies of critical files and folders.
Split into simpler sentences: Backup can be used in connection with either a user's online. Mac iDisk or the Macintosh's CD-RW or DVD-R drive to make safe, archival copies of critical files and folders.