Shutterfly share sites allow users to create online photo albums that can be shared with others. To create a share site, users first log into their Shutterfly account and click "Share Site." They then select a category, enter a name for the site, choose who can view it, and click "Continue." This creates the share site where photos can be uploaded and viewed by those given access. The article provides instructions for how to use Shutterfly's share site feature to easily share photos online.