How do backups work in Picasa and whats a “Backup Set”?
It is critical to do backups of your photos. Simply installing Picasa on your computer does not create extra copies of your photos. Picasa doesn’t automatically back up photos to other disks or to any Google or Picasa web servers. Here’s the basic, official Picasa Backup documentation. What follows here is a more in-depth tutorial-like discussion of backing up and restoring. In Picasa, you define Backup Sets. A Backup Set is a thing you define when you want to back up your photos. A Backup Set definition specifies the destination of a backup (CD/DVD, external disk, networked disk, or local disk). When you “do a backup,” you select a particular backup set. Picasa keeps track of what photos have already been backed up using that backup set. If the Backup Set you select to use is “new” (a just-created backup set, or a backup set that hasn’t been used before), the backup you’re now doing will be a full backup – that is, all photos will be backed up. If the Backup Set you select to use has
