--- a/primer/Primer.html	Tue Oct 25 16:03:37 2011 +0100
+++ b/primer/Primer.html	Thu Oct 27 15:50:47 2011 +0100
@@ -173,9 +173,23 @@
    </section>
 
    <section>
-    <h3>Used and WasGeneratedBy</h3>
+    <h3>Use and Generation</h3>
 
-    <p>An intuitive overview of how to think about use and generation events in Prov-DM.</p>
+    <p>
+     The event of an entity coming into existence is called its <i>generation</i>.
+     The entity will be generated as part of some process execution, e.g. writing
+     a document brings the document into existence, while revising the document brings a new
+     version into existence.
+    </p>
+    <p>
+     Process executions also make use of entities. For example, revising a document
+     requires the original version of the document, the corrections to be made,
+     the new material to be added, etc.
+    </p>
+    <p>
+     In Prov-DM, assertions are made that particular process executions used or generated
+     particular entities.
+    </p>
    </section>
 
    <section>
@@ -329,7 +343,7 @@
    </section>
 
    <section>
-    <h3>Used and WasGeneratedBy</h3>
+    <h3>Use and Generation</h3>
 
     <p>Finally, the Prov data asserts that the chart was generated by this compilation
      process, the compilation process made use of GovData, and the chart was