Find the pictures you forgot you had. Picasa organizes your entire collection while you watch, scanning the images on your computer and automatically sorting them by date. Move and re-name pictures from inside Picasa.
Want to clean up messy folders and move pictures around on your computer’s hard drive? Simply drag and drop pictures from one folder in Picasa to another. Picasa will make the change permanent after double-checking with you.
Want to change a picture’s filename from 671056398a.jpg to Lisa.jpg? In Picasa, it only takes seconds to re-name one picture or a group of pictures. Make a label. Use labels to tag your photos into quick groupings inside Picasa. Viewing and sharing the pictures you grouped under a label is easy – they make great slide shows and movies or you can email them to friends.
Add a star rating. Give a gold star to any photo you love: it turns your favorites into visual standouts at a glance. Picasa even has a star search that reduces your entire photo collection to the best of the best in less than a second.
Keep one picture in multiple albums. Picasa creates a new “instance” of each photo you label without taking up more space on your computer, so you can put the same picture into multiple albums.
Password-protect collections. Have photos you want to keep to yourself? You can add passwords to any of your Picasa collections (this does not affect which pictures you and others can see on your computer’s hard drive).

Picasa for Mac can transfer, find, organize, share, print, and edit images, all with this easy-to-use product. Watch Picasa automatically organize all your pictures into elegant albums by date. Having all your photos in one place means no more time wasted searching for folders or files. The program works with JPEG, GIF, BMP, PSD, and movie files and is compatible with most digital cameras; it detects your USB driver and imports pictures into albums.
Features and Highlights
Share and name tags on Google+
If you've joined Google+, you can use Picasa for macOS to share directly to the circles you've created in Google+. With the release of the software, you can now upload and share your name tags on Google+. Note that if you choose not to join Google+, name tags won't change at all.
Beautiful web albums
Show your photos at their best. View full-screen slideshows, see your pictures arranged on a global map, enjoy video playback, and more.
Sharing made simple
Publish your favorite photos online with one click. Create stunning online photo albums to share with friends and family, or public albums for the world to see. Get notified when your 'Favorites' post new photos.
Focus on people
People matter in your photos. This technology helps you automatically organize your photos based on the people in them, and works in the tool and the app Web Albums.
Edit to perfection
Improve almost any picture with the tool's one-click fixes for common problems like red-eye, color, and lighting. Or, use tuning and effects to make your best photos look even better.
Get organized
Picasa for Mac automatically finds all the photos on your PC, wherever they are and will organize them in seconds.
Add places
Easily add geo-tags to your photos so that you can remember exactly where they're from using Google Maps.
It's free to use
The app is free to download, and Picasa Web Albums provides 1 gigabyte of free storage -- that's enough space for 4,000 wallpaper-size photos.
Note: The application is not developed actively anymore.
Also Available: Download Picasa for Windows