StatCounter, a free online visitor stats tool. It offers its members the chance to grow and improve their online businesses by allowing them to monitor the number of hits to their website; the geographical location of visitors; the various pages a visitor views; keywords used to find the site plus other features.
A pingback is one of four types of linkback methods for Web authors to request notification when somebody links to one of their documents. This enables authors to keep track of who is linking to, or referring to their articles.
See what your Facebook friends have liked, shared, or commented on across the Web. This includes all variations of Like, Share and Follow Buttons, Embedded Posts, Comments, Activity Feed, Recommendations Feed, Recommendations Bar, Like Box and Facepile.