Usually a trackback comes from a another blog that references on of your posts and the trackback will have a little blurb from the post. Your readers might want to read a new facet on your post or a reaction. So these trackbacks are very interesting and attractive to bloggers.
The process is simple as well and it looks like entering a comment. But rather than me retelling, watch the video and perhaps start getting proper trackbacks and links!
This site is Psolenoid activated now. I also left a trackback on Psolenoid blog via this method!
Psolenoid from psolenoid on Vimeo.