--- a/rdf-primer/index.html	Thu Nov 28 15:42:06 2013 +0000
+++ b/rdf-primer/index.html	Thu Nov 28 15:42:42 2013 +0000
@@ -282,12 +282,22 @@
                 alt="Informal graphs of the sample triples">
       <figcaption>Informal graph of the sample triples</figcaption>
     </figure>
+ 
+    <p>The example above does not constitute actual RDF
+    syntax; it is just intended to provide an very informal
+    view of the notion of an RDF graph. </p>
 
-    <!--
-    <p>In the following sections we discuss the three basic constructs
-    that appear in triples, namely IRIs, literals and blank
-    nodes, in more detail. </p> 
-    -->
+    <p class="note">The RDF Data Model is described in this section
+    in the form of an "abstract syntax", i.e. a data model that is independent of a
+    particular encoding.  Different encodings may 
+    produce exactly the same graph from the perspective of the
+    abstract syntax. The semantics of RDF graphs [[RDF11-MY]] are defined in
+    terms of this abstract syntax. RDF syntax is introduced
+    later in Sec. <a href="#section-graph-syntax">Writing RDF
+    graphs</a>.</p>
+
+    <p>In the next three subsections we discuss the three types of RDF data
+    that occur in triples: IRIs, literals and blank nodes. </p>
     
     </section>
 
@@ -479,7 +489,7 @@
     </code>ex:Person</code>. <p>
 
     <p>RDF Schema uses the notion of "class" to
-    specify categories that can be used to classifiy resources. The
+    specify categories that can be used to classify resources. The
     term "property" is used to model predicates.  The main modeling
     constructs in RDF Schema are listed in the table below:
 
@@ -496,12 +506,12 @@
     </tr>
     <tr>
       <td><em>Class</em> (a class)</td>
-      <td><code><strong>s</strong> rdf:type rdfs:Class</code></td>
+      <td><strong>s</strong> <code>rdf:type rdfs:Class</code></td>
       <td><strong>s</strong> (a resource) is an RDF class</td>
     </tr>
     <tr>
       <td><em>Property</em> (a class)</td>
-      <td><code><strong>p</strong> rdf:type rdf:Property</code></td>
+      <td><strong>p</strong> <code>rdf:type rdf:Property</code></td>
       <td><strong>p</strong> (a resource) is an RDF property</td>
     </tr>
     <tr>
@@ -601,7 +611,7 @@
     <h2>Writing RDF graphs</h2>
 
     <p>Many different concrete syntaxes exist for writing down RDF
-    graphs. However, different encodings of the smae graph lead
+    graphs. However, different encodings of the same graph lead
     to exactly the same triples. </p>
 
     <p>In the next two
@@ -620,7 +630,7 @@
     </p>
 
    <p class="issue">
-    TODO: Add example with a bnode, here or in Appenxix.
+    TODO: Add example with a bnode, here or in Appendix.
     </p>
 
     <section id="subsection-turtle">
@@ -719,7 +729,7 @@
 <p class="note">For technical reasons the datatype of language-tagged
 strings is not <code>xsd:string</code> but
 <code>rdf:langString</code>. The
-datatype of language-tagged strings is never specifed explictly
+datatype of language-tagged strings is never specified explicitly
 in Turtle.</p>
 
 <p>The above is by no means a full account of the Turtle syntax. For