hmm, explaining this with figures will probably get me in trouble with my boss. Sorry!
It's all pretty complicated stuff and this is made apparent after a quick glance over all the images available in this document:
If you really want to get in depth on this technology you're probably best off to print out the pdf supplied above and have a good read during the weekend. Not only the tool has some pretty advanced technology also the logs that it produce take a lot of training to interpret.