--- a/rdf-primer/index.html Tue Nov 12 14:34:55 2013 +0100
+++ b/rdf-primer/index.html Tue Nov 12 17:26:03 2013 +0100
@@ -507,8 +507,9 @@
</tbody>
</table>
-<p class="note">The syntactic is a prefix notation wich will be
-discussed in more detail in Sec. <a href="">"Writing RDF
+<p class="note">The syntactic form (thrid column) is in a prefix
+notation wich will be
+discussed in more detail in Sec. <a href="#section-graph-syntax">"Writing RDF
Graphs"</a>. The fact that the constructs have two different prefixes
(<code>rdf:</code> and <code>rdfs:</code>) is a somewhat annoying
historical artefact, which is preserved for backward
@@ -525,7 +526,7 @@
<is a good friend of> <subPropertyOf> <is a friend of>
</pre>
-<p>One of first RDF Schemas used worldwide is the
+<p>One of first RDF Schemas used worldwide was the
<a href="http://www.foaf-project.org/">"Friend of a Friend"</a> (FOAF)
schema for describing social networks. Other examples of RDF
vocabularies are:</p>
@@ -570,28 +571,33 @@
</section>
-
<section id="section-graph-syntax">
<h2>Writing RDF graphs</h2>
- <p>RDF graphs can be expressed in many syntactic forms.
- We give an overview of these various syntaxes below, and illustrate
- them using the example above.</p>
+ <p>Many different concrete syntaxes exist for RDF. In the next two
+ subsections we show RDF syntax examples using the Turtle and Trig
+ language, because these two languages are best suited for human
+ consumption. The final subsection lists the other RDF syntaxes,
+ which include RDFa (for HTML embedding), JSON-LD,
+ N-Triples/N-Quads (line-based exchange formats) and RDF/XML. In
+ Appendix <a href="#section-other-syntaxes">"RDF syntax
+ examples"</a> the reader can find for each RDF syntax
+ corresponding examples of the Turtle/TriG examples in this
+ section. </p>
<section id="subsection-turtle">
<h3>Turtle</h3>
- <p>Turtle [[TURTLE]] provides a convenient syntax for RDF graphs, introducing numerous
- syntax shortcuts, such as the
+ <p>Turtle [[TURTLE]] provides a syntax for RDF
+ graphs, which is convenient for humans. Turtle It introduces numerous
+ syntax shortcuts, such as
support for namespaces, lists and shorthands for datatyped
literals. Turtle provides a good trade-off between ease of
writing, ease of parsing and readability. Our single-graph example can be
represented in Turtle as follows.</p>
- <p>@@ explain example step-by-step</p>
-
<pre class="example" id="turtle-example">
01 @base <http://example.org/> .
02 @prefix foaf: <http://xmlns.com/foaf/0.1/> .
@@ -615,16 +621,35 @@
20
21 <http://data.europeana.eu/item/04802/243FA8618938F4117025F17A8B813C5F9AA4D619>
22 dcterms:subject wd:Q12418 .
- </pre>
+</pre>
- </section>
+<p>Lines 1-6 contain a number of directives which provide shorthands for
+writing down IRIs. A URI like <code>http://xmlns.com/foaf/0.1/</code>
+is colloquially called a namespace URI, in this case of the FOAF
+vocabulary. The "base" prefix is used if no prefix is provided
+(see <code>bob#me</code>on line 8). A period is used to signal the end
+of a Turtle sentence. </p>
+
+<p>Lines 8-12 show how Turtle provides a shorthand for a group of
+triples about the same subject. Lines 9-12 specify predicate-object
+part of triples with <code>http://example.org/bob#me</code> as
+subject. The semicolon at the end of lines 9-11 indicate that the
+group is not yet complete. This is the triple represented by line 10 in its expanded form:</p>
+<pre>
+http://example.org/bob#me http://xmlns.com/foaf/0.1/knows http://example.org/alice#me .
+</pre>
+<p>
+
+
+</section>
<section id="subsection-trig">
<h3>TriG</h3>
<p>TriG [[TRIG]] is an extension to the Turtle syntax enabling
- the exchange of multiple graphs in the form of RDF datasets. For example we could write
+ the exchange of multiple graphs in the form of RDF datasets. For
+ example we could write
our multi-graph example in TriG as follows.</p>
<pre class="example" id="trig-example">
@@ -709,7 +734,7 @@
<section id="section-semantics">
- <h2>RDF Graphs and what you can do with them</h2>
+ <h2>Semantics of RDF Graphs</h2>
<p>@@ example: derive that Alice is a person</p>
@@ -730,7 +755,7 @@
<h2>Document roadmap</h2>
</section>
-<section id="section-syntaxes" class="appendix">
+<section id="section-other-syntaxes" class="appendix">
<h2>Examples of RDF syntaxes</h2>