What is a TRACKBACK?

A Trackback 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 programs, such as Tattertools, Wordpress, Movable Type and Community Server, support automatic pingbacks where all the links in a published article can be pinged when the article is published. The term is used colloquially for any kind of Linkback.

from wikipedia