<div>
  <h1>About the XML namespace</h1>
  <div class="bodytext">
    <p>This schema document describes the XML namespace, in a form suitable for import by other schema documents.</p>
    <p>See
      <a href="http://www.w3.org/XML/1998/namespace.html">http://www.w3.org/XML/1998/namespace.html</a>and
      <a href="http://www.w3.org/TR/REC-xml">http://www.w3.org/TR/REC-xml</a>for information about this namespace.</p>
    <p>Note that local names in this namespace are intended to be defined only by the World Wide Web Consortium or its subgroups. The names currently defined in this namespace are listed below. They should not be used with conflicting semantics by any Working Group, specification, or document instance.</p>
    <p>See further below in this document for more information about
      <a href="#usage">how to refer to this schema document from your own XSD schema documents</a>and about
      <a href="#nsversioning">the namespace-versioning policy governing this schema document</a>.</p>
  </div>
</div>

<div>
  <h3>Father (in any context at all)</h3>
  <div class="bodytext">
    <p>denotes Jon Bosak, the chair of the original XML Working Group. This name is reserved by the following decision of the W3C XML Plenary and XML Coordination groups:</p>
    <blockquote>
      <p>In appreciation for his vision, leadership and dedication the W3C XML Plenary on this 10th day of February, 2000, reserves for Jon Bosak in perpetuity the XML name "xml:Father".</p>
    </blockquote>
  </div>
</div>

<div xml:id="usage" id="usage">
  <h2>
    <a name="usage">About this schema document</a>
  </h2>
  <div class="bodytext">
    <p>This schema defines attributes and an attribute group suitable for use by schemas wishing to allow
      <code>xml:base</code>,
      <code>xml:lang</code>,
      <code>xml:space</code>or
      <code>xml:id</code>attributes on elements they define.</p>
    <p>To enable this, such a schema must import this schema for the XML namespace, e.g. as follows:</p>
    <pre><schema . . .> . . . <import namespace="http://www.w3.org/XML/1998/namespace" schemaLocation="http://www.w3.org/2001/xml.xsd"/></pre>
    <p>or</p>
    <pre><import namespace="http://www.w3.org/XML/1998/namespace" schemaLocation="http://www.w3.org/2009/01/xml.xsd"/></pre>
    <p>Subsequently, qualified reference to any of the attributes or the group defined below will have the desired effect, e.g.</p>
    <pre><type . . .> . . . <attributeGroup ref="xml:specialAttrs"/></pre>
    <p>will define a type which will schema-validate an instance element with any of those attributes.</p>
  </div>
</div>

<div id="nsversioning" xml:id="nsversioning">
  <h2>
    <a name="nsversioning">Versioning policy for this schema document</a>
  </h2>
  <div class="bodytext">
    <p>In keeping with the XML Schema WG's standard versioning policy, this schema document will persist at
      <a href="http://www.w3.org/2009/01/xml.xsd">http://www.w3.org/2009/01/xml.xsd</a>.</p>
    <p>At the date of issue it can also be found at
      <a href="http://www.w3.org/2001/xml.xsd">http://www.w3.org/2001/xml.xsd</a>.</p>
    <p>The schema document at that URI may however change in the future, in order to remain compatible with the latest version of XML Schema itself, or with the XML namespace itself. In other words, if the XML Schema or XML namespaces change, the version of this document at
      <a href="http://www.w3.org/2001/xml.xsd">http://www.w3.org/2001/xml.xsd</a>will change accordingly; the version at
      <a href="http://www.w3.org/2009/01/xml.xsd">http://www.w3.org/2009/01/xml.xsd</a>will not change.</p>
    <p>Previous dated (and unchanging) versions of this schema document are at:</p>
    <ul>
      <li>
        <a href="http://www.w3.org/2009/01/xml.xsd">http://www.w3.org/2009/01/xml.xsd</a>
      </li>
      <li>
        <a href="http://www.w3.org/2007/08/xml.xsd">http://www.w3.org/2007/08/xml.xsd</a>
      </li>
      <li>
        <a href="http://www.w3.org/2004/10/xml.xsd">http://www.w3.org/2004/10/xml.xsd</a>
      </li>
      <li>
        <a href="http://www.w3.org/2001/03/xml.xsd">http://www.w3.org/2001/03/xml.xsd</a>
      </li>
    </ul>
  </div>
</div>

<div>
  <h3>lang (as an attribute name)</h3>
  <p>denotes an attribute whose value is a language code for the natural language of the content of any element; its value is inherited. This name is reserved by virtue of its definition in the XML specification.</p>
</div>
<div>
  <h4>Notes</h4>
  <p>Attempting to install the relevant ISO 2- and 3-letter codes as the enumerated possible values is probably never going to be a realistic possibility.</p>
  <p>See BCP 47 at
    <a href="http://www.rfc-editor.org/rfc/bcp/bcp47.txt">http://www.rfc-editor.org/rfc/bcp/bcp47.txt</a>and the IANA language subtag registry at
    <a href="http://www.iana.org/assignments/language-subtag-registry">http://www.iana.org/assignments/language-subtag-registry</a>for further information.</p>
  <p>The union allows for the 'un-declaration' of xml:lang with the empty string.</p>
</div>

<div>
  <h3>space (as an attribute name)</h3>
  <p>denotes an attribute whose value is a keyword indicating what whitespace processing discipline is intended for the content of the element; its value is inherited. This name is reserved by virtue of its definition in the XML specification.</p>
</div>

<div>
  <h3>base (as an attribute name)</h3>
  <p>denotes an attribute whose value provides a URI to be used as the base for interpreting any relative URIs in the scope of the element on which it appears; its value is inherited. This name is reserved by virtue of its definition in the XML Base specification.</p>
  <p>See
    <a href="http://www.w3.org/TR/xmlbase/">http://www.w3.org/TR/xmlbase/</a>for information about this attribute.</p>
</div>

<div>
  <h3>id (as an attribute name)</h3>
  <p>denotes an attribute whose value should be interpreted as if declared to be of type ID. This name is reserved by virtue of its definition in the xml:id specification.</p>
  <p>See
    <a href="http://www.w3.org/TR/xml-id/">http://www.w3.org/TR/xml-id/</a>for information about this attribute.</p>
</div>