Adopt change 1.S3 proposed by the GLD WG in #254.

spec/latest/json-ld/index.html

@@ -242,6 +242,18 @@ <h2>How to Read this Document</h2>
 
     <p>To understand the basics in this specification you must first be familiar with
       JSON, which is detailed in [[!RFC4627]].</p>
+
+    <p>This document almost exclusively uses the term IRI 
+    (<a href="http://www.w3.org/TR/ld-glossary/#internationalized-resource-identifier">Internationalized Resource Indicator</a>) 
+    when discussing hyperlinks. Many Web developers are more familiar with the 
+    URL (<a href="http://www.w3.org/TR/ld-glossary/#uniform-resource-locator">Uniform Resource Locator</a>) 
+    terminology. The document also uses, albeit rarely, the URI 
+    (<a href="http://www.w3.org/TR/ld-glossary/#uniform-resource-identifier">Uniform Resource Indicator</a>) 
+    terminology. While these terms are often used interchangeably among 
+    technical communities, they do have important distinctions from one
+    another and the specification goes to great lengths to try and use the
+    proper terminology at all times.
+    </p>
   </section>
 </section>