Hi Jennifer,
every time a backup is generated it's stored inside the course files area (click "Files" in course main page) under a directory named "backupdata". This is true if you are talking about manual backups. Also, when the manual backup process ends, there is a link (bottom page) that you can use to go to that "destination" dir directly.
In scheduled backups, there is a file to specify a manual destination. If you leave that field empty, backup files will be written to each "backupdata" dir inside every course (just as manual backup does). Obviously, if a manual destination is specified, then all backup files will go to that place...
Ciao