This link is a "shared" link between the Header, Footer and Sidebox.<br /><br />

The number on the order was set to 50 on all of the settings just for the sake of an easier notation on entering it.<br /><br />

The order can be the same or different for the three locations.<br /><br />

If you wanted to really get creative, you could also have this as part of a Chapter not related to the link order.<br /><br />