--- a/model/ProvenanceModel.html	Wed Jul 27 09:20:55 2011 +0100
+++ b/model/ProvenanceModel.html	Wed Jul 27 12:27:33 2011 +0100
@@ -689,6 +689,26 @@
 
 <p>It is OPTIONAL to assert time in use, generation, and process execution.</p>
 
+<section>
+<h4>Temporal Events</h4>
+Four kinds of discrete events underpin the provenance language. They are:
+<ol>
+<li>Generation of a BOB by a process execution:  identifies the final instant of a BOB's creation timespan, after which the characterized entity represented by a BOB becomes available for use.</li>
+<li>Use of a BOB by a process execution:  identifies the first instant of a BOB's consumption timespan.</li>
+<li>Start of a process execution: identifies the instant an activity represented by a the process execution starts</li>
+<li>End of a process execution: identifies the instant an activity represented by a process execution ends</li>
+</ol>
+</section>
+
+<section>
+<h4>Event Ordering</h4>
+
+
+<p><dfn id="dfn-follows">Follows</dfn> is a partial order between events, indicating that an event occurs after another.  For convenience, <dfn id="dfn-follows">precedes</dfn> is defined as the symmetric of follows. </p>
+
+<p>This specification introduces inferences rules allowing such event ordering to be inferred from provenance constructs.</p>
+</section>
+
 
 </section>