The basic concept of trackbacks and trackbacking seems to confuse some folks. Ryan from the MSN Spaces team has written one of the best explanations for trackbacks and trackbacking that I’ve seen to date. Yes, it’s geared towards MSN Spaces blogs but the same concept holds true for other blogging software that provides trackback functionality:

That address you copied from the original post and then pasted into you entry (the one that ended with “.trak”) is called when you click “publish”. An HTTP POST is sent to this address and the permalink URL to your new post is passed along in the body of the request. This adds the URL to the trackback list of the original post. In the Spaces Beta, the trackback addressing the original post is not saved with your new post. This may change in future releases.

As I learned earlier, the MSN Spaces “blog it” link will automatically include a quote of the post you are reading and include the trackback link automatically in the correct space so you don’t even have to hunt it down (on some blogs this is a chore finding the trackback link). and Ryan goes on to address how trackback works from a practical standpoint and even mixes in a dose of Hitchhiker’s Guide to the Galaxy. Good job, Ryan!