If you want to make your site social,This plugin is the best solution.
All in one FaceBook Plugins for WordPress including like button, Recommendations, Activity Feed, Like Box, Facepile, Live Stream, Comments, Login with Faces and will be continued with facebook.
Like Button: The Like button lets users share pages from your site back to their Facebook profile with one click.
Activity Feed: The Activity Feed plugin shows users what their friends are doing on your site through likes and comments.
Recommendations: The Recommendations plugin gives users personalized suggestions for pages on your site they might like.
Like Box: The Like box enables users to like your Facebook Page and view its stream directly from your website.
Login with Faces: The Login with Faces plugin shows profile pictures of the user’s friends who have already signed up for your site in addition to a login button.
Facepile: The Facepile plugin shows profile pictures of the user’s friends who have already signed up for your site.
Comments: The Comments plugin lets users comment on any piece of content on your site.
Live Stream: The Live Stream plugin lets your users share activity and comments in real-time as they interact during a live event.
Trackback from your site.