Nice page but what do priorities do?

This page gives really clear instructions. However, it doesn't say what priorities are, when you would use them or what thier place in the network is. It would be nice if the page started with an explanation and an example of what happens without them.--SaintD 18:44, 10 May 2009 (UTC)

The improvements help a lot. --SaintD 06:14, 18 May 2009 (UTC)