Picasa is a photo organizer, viewer, editor, and uploader. It is made by Google, and there is a web service called Picasa Web Albums that allows you to host your pictures on the net. You can upload any picture from your hard drive using Picasa. The application scans your hard drives automatically and displays all the pictures and videos that it finds. You can optionally change the auto-detection options so that files on certain folders get filtered and don't make it to the main library or so that only certain folders are automatically scanned.
Picasa makes it really easy to scroll through your pictures. I often find it easier to use than other photo viewers. With your mouse you can scroll through the photos on a single album and, when you make it to the last picture, it automatically goes to the next album. The application can also make it easy for you to download pictures from cameras, camcorders, and even media cards.
These past few months, Picasa has acquired several advanced features. The most impressive ones are connected with tagging. In version 3.6, you can tag people's faces on your pictures. Then, Picasa will scan all your pictures and automatically detect the faces indicated. Additionally, it can group photos with known faces or even find photos with, say, two known faces in them. So if you want to find all the pictures in your collection with you and a friend on them, it is as easy as telling Picasa to do it.
Support for geotagging is very good, and you can use Google Maps to geotag your pictures.
You can share any picture or a batch of them with anyone per e-mail or upload them to Picasa Web Albums, a free service that works great.
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Enjoy a magnificent view of a realistic photo album and share it with friends.
Displays slide shows from public and private Picasa Web Albums.