Folder List: When you are in the Library, the Folder List appears on the left of your screen. The Folder List displays the names of all of the folders Picasa has found on your hard drive.

Folders on Disk are always sorted by date. You will notice that the Folder List contains some categories called Collections, which are a way of automatically organizing the folders on your disk.

When Picasa detects new changes in a folder, a green dot appears to the left of the folder name. To clear the green dot, open the folder.