A pingback is one of three types of linkbacks, 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. Some weblog software, such as Movable Type, Serendipity, WordPress and Telligent Community, support automatic pingbacks where all the links in a published article can be pinged when the article is published.
Essentially, a pingback is an XML-RPC request (not to be confused with an ICMP ping) sent from Site A to Site B, when an author of the blog at Site A writes a post that links to Site B. However, it also requires a hyperlink. When Site B receives the notification signal, it automatically goes back to Site A checking for the existence of a live incoming link. If that link exists, the pingback is recorded successfully. This makes pingbacks less prone to spam than trackbacks. Pingback-enabled resources must either use an X-Pingback header or contain a
<link> element to the XML-RPC script.