--- a/ttml-ww-profiles/ttml-ww-profiles.html	Wed Oct 07 16:12:46 2015 -0700
+++ b/ttml-ww-profiles/ttml-ww-profiles.html	Wed Oct 07 16:52:15 2015 -0700
@@ -830,17 +830,25 @@
 
         <p>An <code>ittp:aspectRatio</code> attribute is considered to be significant only when specified on the <code>tt</code>
         element.</p>
-				
-<div class="example"><div class="example-title"><span>Example 2</span></div><pre class="example">&lt;tt
+
+<aside class="example"><div class="example-title"><span>Example 2</span></div>
+<p>Region <code>"A"</code> in the following document would be positioned 20% from the left edge of a <a href="#dfn-related-video-object" class="internalDFN" data-link-type="dfn">Related Video Object</a> with aspect ratio of 16:9.</p>
+<pre>&lt;tt
   xmlns="http://www.w3.org/ns/ttml"
   xmlns:ttm="http://www.w3.org/ns/ttml#metadata" 
   xmlns:tts="http://www.w3.org/ns/ttml#styling"
   xmlns:ttp="http://www.w3.org/ns/ttml#parameter" 
   xmlns:ittp="http://www.w3.org/ns/ttml/profile/imsc1#parameter"
   ittp:aspectRatio="4 3"
+	tts:extent="400px 300px"
  &gt;
  ...
-&lt;/tt&gt;</pre></div>
+ &lt;region id="A" tts:origin="40px 10px" tts:extent="320px 10px"&gt;
+ ...
+&lt;/tt&gt;
+</pre>
+<p>In other words, <code>tts:extent</code>, when present on the <code>tt</code> element, determines the size of <code>"px"</code> units relative to the root container. <code>ttp:aspectRatio</code> is independently used to map the root container to the <a href="#dfn-related-video-object" class="internalDFN" data-link-type="dfn">Related Video Object</a>.
+</p></aside>
     </section>
       <section id="ttp-progressivelyDecodable" typeof="bibo:Chapter" resource="#ttp-progressivelyDecodable" property="bibo:hasPart">
         <h4 id="h-ttp-progressivelydecodable" resource="#h-ttp-progressivelydecodable"><span property="xhv:role" resource="xhv:heading"><span class="secno">6.7.2 </span>ittp:progressivelyDecodable</span></h4>

--- a/ttml-ww-profiles/ttml-ww-profiles.source.html	Wed Oct 07 16:12:46 2015 -0700
+++ b/ttml-ww-profiles/ttml-ww-profiles.source.html	Wed Oct 07 16:52:15 2015 -0700
@@ -460,8 +460,10 @@
 
         <p>An <code>ittp:aspectRatio</code> attribute is considered to be significant only when specified on the <code>tt</code>
         element.</p>
-				
-<pre class='example'>
+
+<aside class='example'>
+<p>Region <code>"A"</code> in the following document would be positioned 20% from the left edge of a <a>Related Video Object</a> with aspect ratio of 16:9.</p>
+<pre>
 &lt;tt
   xmlns=&quot;http://www.w3.org/ns/ttml&quot;
   xmlns:ttm=&quot;http://www.w3.org/ns/ttml#metadata&quot; 
@@ -469,10 +471,15 @@
   xmlns:ttp=&quot;http://www.w3.org/ns/ttml#parameter&quot; 
   xmlns:ittp=&quot;http://www.w3.org/ns/ttml/profile/imsc1#parameter&quot;
   ittp:aspectRatio=&quot;4 3&quot;
+	tts:extent=&quot;400px 300px&quot;
  &gt;
  ...
+ &lt;region id=&quot;A&quot; tts:origin=&quot;40px 10px&quot; tts:extent=&quot;320px 10px&quot;&gt;
+ ...
 &lt;/tt&gt;
 </pre>
+<p>In other words, <code>tts:extent</code>, when present on the <code>tt</code> element, determines the size of <code>"px"</code> units relative to the root container. <code>ttp:aspectRatio</code> is independently used to map the root container to the <a>Related Video Object</a>.
+</aside>
     </section>
       <section id='ttp-progressivelyDecodable'>
         <h4>ittp:progressivelyDecodable</h4>