--- a/model/ProvenanceModel.html	Thu Sep 15 08:58:55 2011 +0100
+++ b/model/ProvenanceModel.html	Thu Sep 15 14:54:34 2011 +0100
@@ -278,6 +278,7 @@
 
 
 <div class='note'>
+  <p>LUC:  just got started on this. I will provide the graphical notation figure consistent with the notation in the figure of sec. 4.3
 <p>It is proposed to write a short overview of the model, so that the reader can get a feel for what the model does. </p>
 <p>A notion of graph</p>
 <p>Typed nodes, entities, process execution, agents, which are respectively representions of characterized things, activities, and characterized things capable of activies. Show their graphical represenation.</p>
@@ -286,6 +287,12 @@
 <p>
 </div>
 
+The following diagram proveds a very high level overview of the PROV-DM. Examples of a set of provenance assertions that conform to this schema are provided in the next section. The fundamental entities in the model are the following:
+<ul>
+  <li><strong>Entities</strong>: these are representations of <em>characterized things</em>, as defined informally above</li>
+  <li><strong>Process Execution </strong>: these represent activities that have an effect on entities, namely they either generate or use one or more entites. Use and generation are modelled by means of the <em>used</em> and the <em>wasGeneratedBy</em> relationships. Activities include not only computations, but also any other type of activity that can be described in terms of their effect on entities.
+  <li><strong>Agents</strong>: these represent particular entities that can be associated to activities. <em>Agents</em> have a generic connotation: their  association with an activity, represented by the <em>controlledBy</em> relationship, can take up various meanings (attribution, responsibility, supervision, management, etc.), which are not individually specified in the model.
+  
 <img src="overview.png"/>
 
     </section>