RDF is a model, not a format

fixes #142

Author: TallTed

spec/index.html

@@ -352,7 +352,7 @@
     <section id="abstract">
       <h2>Abstract</h2>
       <p>
-        RDF is a directed, labeled graph data format for representing information in the
+        RDF is a directed, labeled graph data model for representing information in the
         Web. This specification defines the syntax and semantics of the SPARQL query language for
         RDF. SPARQL can be used to express queries across diverse data sources, whether the data is
         stored natively as RDF or viewed as RDF via middleware. SPARQL contains capabilities for
@@ -377,7 +377,7 @@ <h2>Abstract</h2>
     <section id="introduction">
       <h2>Introduction</h2>
       <p>
-        RDF is a directed, labeled graph data format for representing information in the Web. RDF is
+        RDF is a directed, labeled graph data model for representing information in the Web. RDF is
         often used to represent, among other things, personal information, social networks, metadata
         about digital artifacts, as well as to provide a means of integration over disparate sources of
         information. This specification defines the syntax and semantics of the SPARQL query language