@@ -1,4 +1,4 @@
-<html><head></head><body><section id="app-item-properties-vocab" class="vocab">
+<section id="app-item-properties-vocab" class="vocab">
 	<h3>Manifest properties vocabulary</h3>
 
 	<p>The properties in this vocabulary are usable in the manifest [^item^]
@@ -235,4 +235,3 @@ <h4>switch</h4>
 		</table>
 	</section>
 </section>
-</body></html>
@@ -1,4 +1,4 @@
-<html><head></head><body><section id="app-itemref-properties-vocab" class="vocab">
+<section id="app-itemref-properties-vocab" class="vocab">
 	<h3>Spine properties vocabulary</h3>
 
 	<p>The properties in this vocabulary are usable in the spine [^itemref^] element's
@@ -79,4 +79,3 @@ <h4>Examples</h4>
 		</aside>
 	</section>
 </section>
-</body></html>
@@ -1,4 +1,4 @@
-<html><head></head><body><section id="app-link-vocab" class="vocab">
+<section id="app-link-vocab" class="vocab">
 	<h3>Metadata link vocabulary</h3>
 
 	<p>The properties in this vocabulary are usable in the metadata [^link^]
@@ -186,4 +186,3 @@ <h5>onix</h5>
 		</section>
 	</section>
 </section>
-</body></html>
@@ -1,4 +1,4 @@
-<html><head></head><body><section id="app-meta-property-vocab" class="vocab">
+<section id="app-meta-property-vocab" class="vocab">
 	<h3>Meta properties vocabulary</h3>
 
 	<p>The properties in this vocabulary are usable in the [^meta^]
@@ -145,11 +145,10 @@ <h5>belongs-to-collection</h5>
 							collections.</p>
 						<p>It is also possible to chain these properties using the <a href="#attrdef-refines"><code>refines</code> attribute</a> to indicate that one collection is
 							itself a member of another collection.</p>
-						<p>To allow [=reading systems=] to organize collections and avoid naming collisions (e.g.,
-							unrelated collections might share a similar name, or different editions of a
-							collection could be released), [=EPUB creators=] SHOULD provide an identifier that uniquely
-							identifies the instance of the collection. The <code>dcterms:identifier</code>
-							property must carry this identifier.</p>
+						<p>A unique identifier SHOULD be provided for each instance of a collection using a 
+							<code>dcterms:identifier</code> property. This will allow [=reading systems=] to organize 
+							collections and avoid naming collisions (e.g., unrelated collections might share a similar 
+							name, or different editions of a collection could be released).</p>
 						<p>The collection MAY more precisely define its nature by attaching a <a href="#collection-type"><code>collection-type</code></a> property.</p>
 						<p>The position of the EPUB publication within the collection MAY be provided by
 							attaching a <a href="#group-position"><code>group-position</code> property</a>.</p>
@@ -207,8 +206,8 @@ <h5>collection-type</h5>
 						<p>The <code>collection-type</code> property indicates the form or nature of a
 							collection.</p>
 						<p>When the <code>collection-type</code> value is drawn from a code list or other formal
-							enumeration, [=EPUB creators=] SHOULD attach a <a href="#attrdef-scheme"><code>scheme</code>
-								attribute</a> to identify its source.</p>
+							enumeration, a <a href="#attrdef-scheme"><code>scheme</code>
+								attribute</a> SHOULD be attached to identify its source.</p>
 						<p>This specification also defines the following collection types when no scheme is
 							specified:</p>
 						<dl>
@@ -228,7 +227,7 @@ <h5>collection-type</h5>
 							</dd>
 						</dl>
 						<div class="note">
-							<p>Although [=reading systems=] are not required to support these values, specifying
+							<p>Although [=reading systems=] do not have to support these values, specifying
 								them provides the option to group related [=EPUB publications=] in more meaningful
 								ways.</p>
 						</div>
@@ -379,7 +378,7 @@ <h5>group-position</h5>
 						<p>The <code>group-position</code> property indicates the numeric position in which the
 							[=EPUB publication=] is ordered relative to other works belonging to the same group
 							(whether all EPUB publications or not).</p>
-						<p>[=EPUB creators=] can attach the <code>group-position</code> property to any metadata
+						<p>The <code>group-position</code> property can be attached to any metadata
 							property that establishes the group but it is typically associated with the <a href="#belongs-to-collection"><code>belongs-to-collection</code>
 							property</a>.</p>
 						<p>An EPUB publication can belong to more than one group.</p>
@@ -462,8 +461,8 @@ <h5>identifier-type</h5>
 						<p>The <code>identifier-type</code> property indicates the form or nature of an
 								<code>identifier</code>.</p>
 						<p>When the <code>identifier-type</code> value is drawn from a code list or other formal
-							enumeration, [=EPUB creators=] SHOULD attach a <a href="#attrdef-scheme"><code>scheme</code>
-								attribute</a> to identify its source.</p>
+							enumeration, a <a href="#attrdef-scheme"><code>scheme</code>
+								attribute</a> SHOULD be attached to identify its source.</p>
 					</td>
 				</tr>
 				<tr>
@@ -520,13 +519,13 @@ <h5>The <code>pageBreakSource</code> property</h5>
 				<td>
 					<p>Provides a unique identifier for the source of the page break markers in an <a
 							href="https://www.w3.org/TR/epub/#dfn-epub-publication">EPUB publication</a>.</p>
-					<p>The identifier should be expressed as a URN when the value conforms to a recognized
+					<p>It is advised to use a URN as the value when the identifier conforms to a recognized
 						scheme such as an ISBN.</p>
-					<p>If a unique identifier does not exist for the source, EPUB creators should use a text
-						description that identifies the source as clearly as possible (e.g., the title of a word
+					<p>If a unique identifier does not exist for the source, it is advised to use a text description 
+						that identifies the source as clearly as possible (e.g., the title of a word
 						processing document).</p>
 					<p>If the page break markers are unique to the EPUB publication (e.g., for a digital-only
-						edition), EPUB creators MUST specify the value "<code>none</code>".</p>
+						edition), the value "<code>none</code>" MUST be specified.</p>
 				</td>
 			</tr>
 			<tr>
@@ -598,12 +597,12 @@ <h5>role</h5>
 								<code>contributor</code> or <code>publisher</code> in the creation of an EPUB
 							publication.</p>
 						<p>When the <code>role</code> value is drawn from a code list or other formal
-							enumeration, [=EPUB creators=] SHOULD attach a <a href="#attrdef-scheme"><code>scheme</code>
-								attribute</a> to identify its source.</p>
-						<p>When attaching multiple roles to an individual or organization, the importance of the
-							roles should match the document order of their containing <code>meta</code> elements
-							(i.e., the first <code>meta</code> element encountered should contain the most
-							important role).</p>
+							enumeration, a <a href="#attrdef-scheme"><code>scheme</code>
+								attribute</a> SHOULD be attached to identify its source.</p>
+						<p>When assigning multiple roles to an individual or organization, associate each role in a
+							separate <code>meta</code> element and ensure the document order of the elements reflects
+							the importance of the roles played (i.e., the first <code>meta</code> element encountered
+							contains the most important role).</p>
 					</td>
 				</tr>
 				<tr>
@@ -681,12 +680,12 @@ <h5>role</h5>
 	</section>
 	<section id="sec-source-of" data-epubcheck="true" data-tests="https://w3c.github.io/epub-structural-tests/#D-vocabularies_meta-properties.feature_L170,https://w3c.github.io/epub-structural-tests/#D-vocabularies_meta-properties.feature_L175,https://w3c.github.io/epub-structural-tests/#D-vocabularies_meta-properties.feature_L182,https://w3c.github.io/epub-structural-tests/#D-vocabularies_meta-properties.feature_L189,https://w3c.github.io/epub-structural-tests/#D-vocabularies_meta-properties.feature_L196">
 		<h5>source-of</h5>
-		<p>The <code>source-of</code> property is no longer recommended for use in EPUB publications. To indicate
+		<p>It is no longer advised to use the <code>source-of</code> property in EPUB publications. To indicate
 			the source of pagination for an EPUB publication, refer to the <a 
 				href="#sec-pageBreakSource"><code>pageBreakSource</code> property definition</a>.</p>
 		<div class="note">
 			<p>The <code>source-of</code> property will not be officially deprecated due to the existing base of EPUB 
-				publications in which it is used, but it should be treated by EPUB creators as though it is deprecated.
+				publications in which it is used, but it is advised to treat it as though it is deprecated.
 				For information on its use, refer to <a data-cite="epub-33#source-of"><code>source-of</code> property 
 					definition</a> in [[epub-33]].</p>
 		</div>
@@ -765,8 +764,8 @@ <h5>title-type</h5>
 						<p>The <code>title-type</code> property indicates the form or nature of a
 								<code>title</code>.</p>
 						<p>When the <code>title-type</code> value is drawn from a code list or other formal
-							enumeration, [=EPUB creators=] SHOULD attach a <a href="#attrdef-scheme"><code>scheme</code>
-								attribute</a> to identify its source. When a scheme is not specified, [=reading systems=]
+							enumeration, a <a href="#attrdef-scheme"><code>scheme</code>
+								attribute</a> SHOULD be attached to identify its source. When a scheme is not specified, [=reading systems=]
 								SHOULD recognize the following title type values:
 								<code>main</code>, <code>subtitle</code>, <code class="value">short</code>,
 								<code>collection</code>, <code class="value">edition</code> and
@@ -979,4 +978,3 @@ <h5>Examples</h5>
 		</aside>
 	</section>
 </section>
-</body></html>
@@ -1,4 +1,5 @@
-<html><head></head><body><section id="app-overlays-vocab" class="vocab">
+
+<section id="app-overlays-vocab" class="vocab">
 	<h3>Media overlays vocabulary</h3>
 	<p>The properties in this vocabulary are usable in the [^meta^] element's
 			<code>property</code> attribute.</p>
@@ -18,7 +19,7 @@ <h4>active-class</h4>
 				</tr>
 				<tr>
 					<th>Description:</th>
-					<td>[=EPUB creator=]-defined CSS class name to apply to the currently playing [=EPUB content document=]
+					<td>The CSS class name to apply to the currently playing [=EPUB content document=]
 						element.</td>
 				</tr>
 				<tr>
@@ -152,4 +153,3 @@ <h4>playback-active-class</h4>
 		</table>
 	</section>
 </section>
-</body></html>
@@ -1,4 +1,4 @@
-<html><head></head><body><section id="app-rendering-vocab">
+<section id="app-rendering-vocab">
 	<h3>Package rendering vocabulary</h3>
 
 	<p>The prefix URL for <a href="#sec-default-vocab">referencing these properties</a> is
@@ -97,18 +97,16 @@ <h3>Package rendering vocabulary</h3>
 	<section id="sec-rendering-custom-properties" data-epubcheck="true" data-tests="https://w3c.github.io/epub-structural-tests/#D-vocabularies_package-rendering-vocab.feature_L19">
 		<h4>Custom rendering properties</h4>
 
-		<p>[=Reading system=] developers may introduce functionality not defined in this specification to address 
-			reading system-specific issues rendering [=EPUB content documents=].</p>
+		<p>Custom properties and [=EPUB spine | spine=] overrides can be included in the 
+			[=package document=] to address rendering issues specific to particular 
+			[=reading systems=], as defined by the developers of those reading systems.</p>
 
-		<p>To facilitate this experimentation, [=EPUB creators=] MAY include custom properties and [=EPUB spine | spine=]
-			overrides for use in the [=package document=] provided they do not use the <code>rendition:</code>
-			prefix.</p>
-		
-		<div class="note">
-			<p>Custom properties should only address rendering issues specific to a particular reading system. This
-				specification should be extended to provide extensions that multiple independent reading systems can
-				use.</p>
-		</div>
+		<p>The only restrictions are that such properties MUST NOT be defined with a 
+			<code>rendition:</code> prefix and MUST NOT conflict behaviorally with properties 
+			in the <a href="app-rendering-vocab">package rendering vocabulary</a>.</p>
+			
+		<p>If extensions are needed for use by multiple independent reading systems, the 
+			preferred method is to extend the package rendering vocabulary through a revision 
+			to this standard.</p>
 	</section>
 </section>
-</body></html>
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="en-US">
+<html lang="en-US" xmlns="http://www.w3.org/1999/xhtml">
 	<head>
 		<meta charset="utf-8" />
 		<title>EPUB 3 Overview</title>
@@ -651,9 +651,9 @@ <h3>Notes</h3>
 						EPUB Accessibility 1.1.1 [[epub-a11y-111]] discovery and accessibility requirements for EPUB
 						publications. </li>
 					<li>
-						[[[epub-a11y-exemption]]] [[epub-a11y-exemption]]: the <code>exemption</code> property allows EPUB creators to indicate that an EPUB publication that does
-						not meet accessibility conformance requirements has an exemption under the applicable jurisdiction's
-						laws.
+						[[[epub-a11y-exemption]]] [[epub-a11y-exemption]]: the <code>exemption</code> property is used
+						to indicate that an EPUB publication that does not meet accessibility conformance requirements
+						has an exemption under the applicable jurisdiction's laws.
 					</li>
 					<li>
 						[[[epub-fxl-a11y]]] [[epub-fxl-a11y]]: provides guidance on how to make fixed-layout EPUB publications accessible.