w3c
diff --git a/‎selectors/Overview.bs‎
Lines changed: 17 additions & 15 deletions b/‎selectors/Overview.bs‎
Lines changed: 17 additions & 15 deletions
@@ -968,7 +968,7 @@ Characters and case sensitivity</h3>
 
 
 <h3 id="namespaces">
-Namespaces</h3>
+Declaring Namespace Prefixes</h3>
 
 	Certain selectors support namespace prefixes.
 	The mechanism by which namespace prefixes are <dfn id="nsdecl">declared</dfn>
@@ -1170,30 +1170,29 @@ Elemental selectors</h2>
 <h3 id="type-selectors">
 Type (tag name) selector</h3>
 
-	A <dfn export>type selector</dfn> is the name of a document language element type
-	written as either an <a>identifier</a>
-	or, if interacting with namespaces,
-	a <a>CSS qualified name</a>
-	(see [[#type-nmsp]])
-	[[!CSS3NAMESPACE]].
-
-	A type selector represents an instance of the element type in the document tree.
+	A <dfn export>type selector</dfn> is the name of a document language element type,
+	and represents an instance of that element type in the document tree.
 
 	<div class="example">
 		For example, the selector ''h1'' represents an <a element>h1</a> element in the document.
 	</div>
 
+	A <a>type selector</a> is written as a <a>CSS qualified name</a>:
+	an <a>identifier</a> with an optional namespace prefix.
+	[[!CSS3NAMESPACE]]
+	(See [[#type-nmsp]].)
+
 <h3 id="the-universal-selector">
 Universal selector </h3>
 
 	The <dfn export>universal selector</dfn> is a special <a>type selector</a>,
-	written either as the asterisk character (<code>*</code> U+002A),
-	or as a <a>CSS qualified name</a>
-	with an asterisk as the local name (see [[#type-nmsp]]).
-	It represents an element with any name.
+	that represents an element of any element type.
 
+	It is written a <a>CSS qualified name</a>
+	with an asterisk (<code>*</code> U+002A) as the local name.
 	Like a <a>type selector</a>,
 	the <a>universal selector</a> can be qualified by a namespace,
+	restricting it to only elements belonging to that namespace,
 	and is affected by a default namespace as defined in [[#type-nmsp]].
 
 	Unless an element is <a>featureless</a>,
@@ -1220,9 +1219,9 @@ Universal selector </h3>
 	but writing the former as ''div *:first-child'' makes the difference obvious.
 
 <h3 id='type-nmsp'>
-Namespaces in Selectors</h3>
+Namespaces in Elemental Selectors</h3>
 
-	<a>Type selectors</a> allow an optional namespace component:
+	<a>Type selectors</a> and <a>universal selectors</a> allow an optional namespace component:
 	a namespace prefix that has been previously <a href="#nsdecl">declared</a>
 	may be prepended to the element name separated by the namespace separator “vertical bar” (<code>|</code> U+007C).
 	(See, e.g., [[XML-NAMES]] for the use of namespaces in XML.)
@@ -1297,6 +1296,9 @@ Namespaces in Selectors</h3>
 		even though no reference to the type name (which is paired with the namespace in the DOM) appeared.
 	</div>
 
+	A <a>type selector</a> or <a>universal selector</a> containing a namespace prefix
+	that has not been previously <a href="#nsdecl">declared</a>
+	is an <a>invalid selector</a>.
 
 <h2 id="attribute-selectors">
 Attribute selectors</h2>