Picasa is a free photo organizing and editing software program from Google. It's compatible on Windows, Mac, and Linux operating systems. Watch the video below to get an introduction to Picasa 3.
Flickr is a free photo managing and sharing Web application aimed at providing users a way to organize and share personal photos with others. Since Flickr is an online application, you are able to use Flickr on any Web browser and can login using an existing Yahoo, Google, or Facebook account.
Flickr's Creative Commons feature grants users the option of securing copy-free images.