What is trackback?
Trackback is a mechanism for communication between blogs. if a blogger is writing a new entry which comments on, orrefers to an entry on another blog, then the commenting blogger can notify the other blog about this. This is known as a 'trackback ping'. The log receiving blog will typically display a list of links to all the commenting entries. You can often see these below the original entry.
Trackback allows a conversations spanning several blogs to be presented in a format which makes it easy to follow.
However, in order for this to work both blogging tools need to support the TrackBack protocol. Some bloggers switch off Trackback as it has created problems with 'trackback spam', which is a false trackback only intended to try and advertise something. Recent version of blogging software have got better at avoiding trackback spam, but the whole issue is still problematic.
