Even after you save, a backup of your original image is just a click away. Picasa's easy-to-use editing tools apply 'virtual edits' to your photos, until you're sure you want to save your changes to disk. And Picasa automatically keeps track of new photos on your hard drive. Picasa for Mac can find and display a huge number of images (now up to a million photos!) from all over your computer. Picasa for Mac scans the photos and videos in both the 'Originals' and 'Modified' folders, and displays a single collective folder with the most recent version of each file. contains an 'Originals' folder and a 'Modified' folder.
Picasa handles the iPhoto Library in the same way, with a small variation made for the way in which the iPhoto Library organizes your photos In this way, Picasa folders represent the actual directories containing photos on your computer's hard drive. Picasa simply scans your hard drive and displays the photo files it finds. Picasa for Mac is a software for organizing and editing digital photos on Mac OS X. IBM Tivoli Continuous Data Protection for Files
