The Social Bookmarking plugin allows users to share links to items in your site with their favorite social networking websites. This plugin is available on all plans.
Configure Social Bookmarking
1. After installing the plugin, click Configure.
2. You will see a long page filled with icons of social bookmarking tools and sites. Click the check boxes of as many services as you wish (such as Facebook, Twitter, Digg, Delicious). Each tiny icon will appear at the bottom of the items/show page for each item (see image below), and allow site visitors to share items on their social networking sites.