Allows to qualify the priority of the requested changes. The priorization model is up to the author. The
SGML processing system can use this element to order the requested changes according to their priority. Therfore the highest priority should be of low lexical order.
It can either be a simple number (high priorities get low values) determining the priority.
Another model is a letter/digit combination. The letter characterizes the importance, the digit the urgency (e.g.
A 2 says
very important and
medium urgent)