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[o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Namespace_names" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Namespace_names"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Namespace names</span> </div> </a> <ul id="toc-Namespace_names-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Namespace_declaration" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Namespace_declaration"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Namespace declaration</span> </div> </a> <ul id="toc-Namespace_declaration-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Namespaces_in_APIs_and_XML_object_models" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Namespaces_in_APIs_and_XML_object_models"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Namespaces in APIs and XML object models</span> </div> </a> <ul id="toc-Namespaces_in_APIs_and_XML_object_models-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">XML namespace</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" 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id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Method of providing unique elements and attributes in an XML document</div> <p><b>XML namespaces</b> are used for providing uniquely named <a href="/wiki/Data_element" title="Data element">elements</a> and attributes in an <a href="/wiki/XML" title="XML">XML</a> document. They are defined in a <a href="/wiki/World_Wide_Web_Consortium" title="World Wide Web Consortium">W3C recommendation</a>.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-timelinehistory_2-0" class="reference"><a href="#cite_note-timelinehistory-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> An XML instance may contain element or attribute names from more than one XML vocabulary. If each vocabulary is given a <a href="/wiki/Namespace" title="Namespace">namespace</a>, the ambiguity between identically named elements or attributes can be resolved. </p><p>A simple example would be to consider an XML instance that contained references to a customer and an ordered product. Both the customer element and the product element could have a child element named <b>id</b>. References to the <b>id</b> element would therefore be ambiguous; placing them in different namespaces would remove the ambiguity. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Namespace_names">Namespace names</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XML_namespace&action=edit&section=1" title="Edit section: Namespace names"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A <i>namespace name</i> is a <a href="/wiki/Uniform_resource_identifier" class="mw-redirect" title="Uniform resource identifier">uniform resource identifier</a> (URI). Typically, the URI chosen for the namespace of a given XML vocabulary describes a resource under the control of the author or organization defining the vocabulary, such as a <a href="/wiki/Uniform_resource_locator" class="mw-redirect" title="Uniform resource locator">URL</a> for the author's Web server. However, the namespace specification does not require nor suggest that the namespace URI be used to retrieve information; it is simply treated by an XML parser as a string. For example, the document at <a rel="nofollow" class="external free" href="http://www.w3.org/1999/xhtml">http://www.w3.org/1999/xhtml</a> itself does not contain any code. It simply describes the <a href="/wiki/XHTML" title="XHTML">XHTML</a> namespace to human readers. Using a URI (such as "http://www.w3.org/1999/xhtml") to identify a namespace, rather than a simple string (such as "xhtml"), reduces the probability of different namespaces using duplicate identifiers. </p><p>Although the term <i>namespace URI</i> is widespread, the W3C Recommendation refers to it as the <i>namespace name</i>. The specification is not entirely prescriptive about the precise rules for namespace names (it does not explicitly say that parsers must reject documents where the namespace name is not a valid <a href="/wiki/Uniform_Resource_Identifier" title="Uniform Resource Identifier">Uniform Resource Identifier</a>), and many XML parsers allow any character string to be used. In version 1.1 of the recommendation, the namespace name becomes an <a href="/wiki/Internationalized_Resource_Identifier" title="Internationalized Resource Identifier">Internationalized Resource Identifier</a>, which licenses the use of non-ASCII characters that in practice were already accepted by nearly all XML software. The term <i>namespace URI</i> persists, however, not only in popular usage, but also in many other specifications from W3C and elsewhere. </p><p>Following publication of the Namespaces recommendation, there was an intensive debate about how a relative URI should be handled, with some intensely arguing that it should simply be treated as a character string, and others arguing with conviction that it should be turned into an absolute URI by resolving it against the base URI of the document.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> The result of the debate was a ruling from W3C that relative URIs were deprecated.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>The use of URIs taking the form of URLs in the http scheme (such as <i><a rel="nofollow" class="external free" href="http://www.w3.org/1999/xhtml">http://www.w3.org/1999/xhtml</a></i>) is common, despite the absence of any formal relationship with the HTTP protocol. The Namespaces specification does not say what should happen if such a URL is dereferenced (that is, if software attempts to retrieve a document from this location). One convention adopted by some users is to place an <a href="/wiki/RDDL" class="mw-redirect" title="RDDL">RDDL</a> document at the location.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> In general, however, users should assume that the namespace URI is simply a name, not the address of a document on the Web. </p> <div class="mw-heading mw-heading2"><h2 id="Namespace_declaration">Namespace declaration</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XML_namespace&action=edit&section=2" title="Edit section: Namespace declaration"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An XML namespace is declared using the reserved XML attribute <code>xmlns</code> or <code>xmlns:<i>prefix</i></code>, the value of which must be a valid <a href="#Namespace_names">namespace name</a>. </p><p>For example, the following declaration maps the "xhtml:" prefix to the XHTML namespace: </p> <pre>xmlns:xhtml="http://www.w3.org/1999/xhtml"</pre> <p>Any element or attribute whose name starts with the prefix "xhtml:" is considered to be in the XHTML namespace, if it or an ancestor has the above namespace declaration. </p><p>It is also possible to declare a default namespace. For example: </p> <pre>xmlns="http://www.w3.org/1999/xhtml"</pre> <p>In this case, any element without a namespace prefix is considered to be in the XHTML namespace, if it or an ancestor has the above default namespace declaration. </p><p>If there is no default namespace declaration in scope, the namespace name has no value.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> In that case, an element without an explicit namespace prefix is considered not to be in any namespace. </p><p>Attributes are never subject to the default namespace. An attribute without an explicit namespace prefix is considered not to be in any namespace. </p> <div class="mw-heading mw-heading2"><h2 id="Namespaces_in_APIs_and_XML_object_models">Namespaces in APIs and XML object models</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XML_namespace&action=edit&section=3" title="Edit section: Namespaces in APIs and XML object models"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Different specifications have taken different approaches on how namespace information is presented to applications. </p><p>Nearly all programming models allow the name of an element or attribute node to be retrieved as a three-part name: the local name, the namespace prefix, and the namespace URI. Applications should avoid attaching any significance to the choice of prefix, but the information is provided because it can be helpful to human readers. Names are considered equal if the namespace URI and local name match. </p><p>In addition, most models provide some way of determining which namespaces have been declared for a given element. This information is needed because some XML vocabularies allow qualified names (containing namespace prefixes) to appear in the content of elements or attributes, as well as in their names. There are three main ways this information can be provided: </p> <ul><li>As attribute nodes named "xmlns" or "xmlns:xxx", exactly as the namespaces are written in the source XML document. This is the model presented by <a href="/wiki/Document_Object_Model" title="Document Object Model">DOM</a>.</li> <li>As namespace declarations: distinguished from attributes, but corresponding one-to-one with the relevant attributes in the source XML document. This is the model presented by <a href="/wiki/JDOM" title="JDOM">JDOM</a>.</li> <li>As in-scope namespace bindings: in this model, the application is able to determine which namespaces are in scope for any given element, but is not able to determine which elements contain the actual declarations. This is the model used in <a href="/wiki/XPath" title="XPath">XPath</a>, <a href="/wiki/XSLT" title="XSLT">XSLT</a>, and <a href="/wiki/XQuery" title="XQuery">XQuery</a>.</li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XML_namespace&action=edit&section=4" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Namespace" title="Namespace">Namespace</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XML_namespace&action=edit&section=5" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFBrayDave_HollanderAndrew_LaymanRichard_Tobin2009" class="citation web cs1">Bray, Tim; Dave Hollander; Andrew Layman; Richard Tobin; Henry S. Thompson (December 2009). <a rel="nofollow" class="external text" href="http://www.w3.org/TR/xml-names/">"Namespaces in XML 1.0"</a>. <a href="/wiki/W3C" class="mw-redirect" title="W3C">W3C</a><span class="reference-accessdate">. Retrieved <span class="nowrap">9 October</span> 2010</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Namespaces+in+XML+1.0&rft.pub=W3C&rft.date=2009-12&rft.aulast=Bray&rft.aufirst=Tim&rft.au=Dave+Hollander&rft.au=Andrew+Layman&rft.au=Richard+Tobin&rft.au=Henry+S.+Thompson&rft_id=http%3A%2F%2Fwww.w3.org%2FTR%2Fxml-names%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXML+namespace" class="Z3988"></span></span> </li> <li id="cite_note-timelinehistory-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-timelinehistory_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.dblab.ntua.gr/~bikakis/XMLSemanticWebW3CTimeline1.2.pdf">"XML and Semantic Web W3C Standards Timeline (v.1.2)"</a> <span class="cs1-format">(PDF)</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=XML+and+Semantic+Web+W3C+Standards+Timeline+%28v.1.2%29&rft_id=http%3A%2F%2Fwww.dblab.ntua.gr%2F~bikakis%2FXMLSemanticWebW3CTimeline1.2.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXML+namespace" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDodds2000" class="citation web cs1">Dodds, Leigh (24 May 2000). <a rel="nofollow" class="external text" href="https://www.xml.com/pub/a/2000/05/24/deviant/index.html">"News from the trenches"</a>. O'Reilly Media, Inc.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=News+from+the+trenches&rft.pub=O%27Reilly+Media%2C+Inc.&rft.date=2000-05-24&rft.aulast=Dodds&rft.aufirst=Leigh&rft_id=https%3A%2F%2Fwww.xml.com%2Fpub%2Fa%2F2000%2F05%2F24%2Fdeviant%2Findex.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXML+namespace" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFConnolly2000" class="citation cs2">Connolly, Dan (11 Sep 2000), <i>W3C XML Plenary decision on relative URI references in namespace declarations</i></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=W3C+XML+Plenary+decision+on+relative+URI+references+in+namespace+declarations&rft.date=2000-09-11&rft.aulast=Connolly&rft.aufirst=Dan&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXML+namespace" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHarold2001" class="citation web cs1">Harold, Elliotte Rusty (20 Feb 2001). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170507150520/http://archive.oreilly.com/pub/a/oreilly/xml/news/xmlnut2_0201.html">"RDDL Me This: What Does a Namespace URL Locate?"</a>. Archived from <a rel="nofollow" class="external text" href="http://www.oreillynet.com/pub/a/oreilly/xml/news/xmlnut2_0201.html">the original</a> on 7 May 2017.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=RDDL+Me+This%3A+What+Does+a+Namespace+URL+Locate%3F&rft.date=2001-02-20&rft.aulast=Harold&rft.aufirst=Elliotte+Rusty&rft_id=http%3A%2F%2Fwww.oreillynet.com%2Fpub%2Fa%2Foreilly%2Fxml%2Fnews%2Fxmlnut2_0201.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXML+namespace" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.w3.org/TR/REC-xml-names/#dt-qualname">"Namespaces in XML 1.0 (Third Edition)"</a>. W3C<span class="reference-accessdate">. Retrieved <span class="nowrap">28 April</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Namespaces+in+XML+1.0+%28Third+Edition%29&rft.pub=W3C&rft_id=https%3A%2F%2Fwww.w3.org%2FTR%2FREC-xml-names%2F%23dt-qualname&rfr_id=info%3Asid%2Fen.wikipedia.org%3AXML+namespace" class="Z3988"></span></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=XML_namespace&action=edit&section=6" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.w3.org/TR/REC-xml-names/">Namespaces in XML 1.0 (Third Edition)</a></li> <li><a rel="nofollow" class="external text" href="http://www.w3.org/TR/2006/REC-xml-names11-20060816/">Namespaces in XML 1.1 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href="/wiki/Simple_Knowledge_Organization_System" title="Simple Knowledge Organization System">SKOS</a></li> <li><a href="/wiki/Synchronized_Multimedia_Integration_Language" title="Synchronized Multimedia Integration Language">SMIL</a></li> <li><a href="/wiki/SOAP" title="SOAP">SOAP</a></li> <li><a href="/wiki/Speech_Recognition_Grammar_Specification" title="Speech Recognition Grammar Specification">SRGS</a></li> <li><a href="/wiki/Subresource_Integrity" title="Subresource Integrity">SRI</a></li> <li><a href="/wiki/Speech_Synthesis_Markup_Language" title="Speech Synthesis Markup Language">SSML</a></li> <li><a href="/wiki/Scalable_Vector_Graphics" class="mw-redirect" title="Scalable Vector Graphics">SVG</a> <ul><li><a href="/wiki/SVG_filter_effects" title="SVG filter effects">Filter Effects</a></li></ul></li> <li><a href="/wiki/SCXML" title="SCXML">SCXML</a></li> <li><a href="/wiki/SHACL" title="SHACL">SHACL</a></li> <li><a href="/wiki/SPARQL" title="SPARQL">SPARQL</a></li> <li><a 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href="/wiki/XML_Base" title="XML Base">Base</a></li> <li><a href="/wiki/XML_Encryption" title="XML Encryption">Encryption</a></li> <li><a href="/wiki/XML_Events" title="XML Events">Events</a></li> <li><a href="/wiki/XML_Information_Set" title="XML Information Set">Information Set</a></li> <li><a class="mw-selflink selflink">Namespace</a></li> <li><a href="/wiki/XML_Schema_(W3C)" title="XML Schema (W3C)">Schema</a></li> <li><a href="/wiki/XML_Signature" title="XML Signature">Signature</a></li> <li><a href="/wiki/XForms" title="XForms">XForms</a></li> <li><a href="/wiki/XInclude" title="XInclude">XInclude</a></li> <li><a href="/wiki/XLink" title="XLink">XLink</a></li> <li><a href="/wiki/XML-binary_Optimized_Packaging" title="XML-binary Optimized Packaging">XOP</a></li> <li><a href="/wiki/XPath" title="XPath">XPath</a> <ul><li><a href="/wiki/XPath_2.0" title="XPath 2.0">2.0</a></li> <li><a href="/wiki/XPath_3" title="XPath 3">3.x</a></li></ul></li> <li><a href="/wiki/XPointer" title="XPointer">XPointer</a></li> <li><a href="/wiki/XProc" title="XProc">XProc</a></li> <li><a href="/wiki/XQuery" title="XQuery">XQuery</a></li> <li><a href="/wiki/XSL" title="XSL">XSL</a></li> <li><a href="/wiki/XSL_Formatting_Objects" title="XSL Formatting Objects">XSL-FO</a></li> <li><a href="/wiki/XSLT" title="XSLT">XSLT</a> <ul><li><a href="/wiki/XSLT_elements" title="XSLT elements">elements</a></li></ul></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Notes</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/IndieAuth" title="IndieAuth">IndieAuth</a></li> <li><a href="/wiki/XAdES" title="XAdES">XAdES</a></li> <li><a href="/wiki/XBL" title="XBL">XBL</a></li> <li><a href="/wiki/XHTML%2BSMIL" title="XHTML+SMIL">XHTML+SMIL</a></li> <li><a href="/wiki/Extensible_User_Interface_Protocol" title="Extensible User Interface Protocol">XUP</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/World_Wide_Web_Consortium#Working_draft_(WD)" title="World Wide Web Consortium">Working drafts</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Call_Control_eXtensible_Markup_Language" title="Call Control eXtensible Markup Language">CCXML</a></li> <li><a href="/wiki/CURIE" title="CURIE">CURIE</a></li> <li><a href="/wiki/Encrypted_Media_Extensions" title="Encrypted Media Extensions">EME</a></li> <li><a href="/wiki/InkML" title="InkML">InkML</a></li> <li><a href="/wiki/Media_Source_Extensions" title="Media Source Extensions">MSE</a></li> <li><a href="/wiki/Rule_Interchange_Format" title="Rule Interchange Format">RIF</a></li> <li><a href="/wiki/SMIL_Timesheets" title="SMIL Timesheets">SMIL Timesheets</a></li> <li><a href="/wiki/SXBL" title="SXBL">sXBL</a></li> <li><a href="/wiki/WebGPU" title="WebGPU">WebGPU</a></li> <li><a href="/wiki/WebXR" title="WebXR">WebXR</a></li> <li><a href="/wiki/Extensible_Forms_Description_Language" title="Extensible Forms Description Language">XFDL</a></li> <li><a href="/wiki/XFrames" title="XFrames">XFrames</a></li> <li><a href="/wiki/XMLHttpRequest" title="XMLHttpRequest">XMLHttpRequest</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Guidelines</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Web_Content_Accessibility_Guidelines" title="Web Content Accessibility Guidelines">Web Content Accessibility Guidelines</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Initiative</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/W3C_Markup_Validation_Service" title="W3C Markup Validation Service">Markup Validation Service</a></li> <li><a href="/wiki/Web_Accessibility_Initiative" title="Web Accessibility Initiative">Web Accessibility Initiative</a></li> <li><a href="/wiki/Web_Components" title="Web Components">Web Components</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Deprecated</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/C-HTML" class="mw-redirect" title="C-HTML">C-HTML</a></li> <li><a href="/wiki/Handheld_Device_Markup_Language" title="Handheld Device Markup Language">HDML</a></li> <li><a href="/wiki/JavaScript_Style_Sheets" title="JavaScript Style Sheets">JSSS</a></li> <li><a href="/wiki/Precision_Graphics_Markup_Language" title="Precision Graphics Markup Language">PGML</a></li> <li><a href="/wiki/Vector_Markup_Language" title="Vector Markup Language">VML</a></li> <li><a href="/wiki/WebPlatform.org" title="WebPlatform.org">WebPlatform</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Obsoleted</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/P3P" title="P3P">P3P</a></li> <li><a href="/wiki/XHTML%2BMathML%2BSVG" title="XHTML+MathML+SVG">XHTML+MathML+SVG</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Organizations</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/World_Wide_Web_Foundation" title="World Wide Web Foundation">World Wide Web Foundation</a></li> <li><a href="/wiki/WHATWG" title="WHATWG">WHATWG</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Elected groups</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/w/index.php?title=W3C_Advisory_Board&action=edit&redlink=1" class="new" title="W3C Advisory Board (page does not exist)">AB</a></li> <li><a href="/w/index.php?title=W3C_Board&action=edit&redlink=1" class="new" title="W3C Board (page does not exist)">Board</a></li> <li><a href="/wiki/Technical_Architecture_Group" title="Technical Architecture Group">TAG</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Working groups</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CSS_Working_Group" title="CSS Working Group">CSS</a></li> <li><a href="/wiki/SVG_Working_Group" title="SVG Working Group">SVG</a></li> <li><a href="/wiki/WebAssembly" title="WebAssembly">WebAssembly</a></li> <li><a href="/wiki/Web_Authentication_Working_Group" title="Web Authentication Working Group">WebAuthn</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Community & business groups</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Improving_Web_Advertising_Business_Group" title="Improving Web Advertising Business Group">Web Advertising BG</a></li> <li><a href="/wiki/WebAssembly" title="WebAssembly">WebAssembly</a> CG</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Closed groups</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/W3C_Device_Description_Working_Group" title="W3C Device Description Working Group">Device Description</a> (DDWG)</li> <li><a href="/wiki/HTML_Working_Group" title="HTML Working Group">HTML</a></li> <li><a href="/wiki/W3C_MMI" title="W3C MMI">Multimodal Interaction Activity</a> (MMI)</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Software</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CERN_httpd" title="CERN httpd">CERN httpd</a></li> <li><a href="/wiki/Libwww" title="Libwww">Libwww</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Web_browser" title="Web browser">Browsers</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Line_Mode_Browser" title="Line Mode Browser">Line Mode</a> <span style="font-size:85%;">(1990–)</span></li> <li><a href="/wiki/Arena_(web_browser)" title="Arena (web browser)">Arena</a> <span style="font-size:85%;">(1993–98)</span></li> <li><a href="/wiki/Agora_(web_browser)" title="Agora (web browser)">Agora</a> <span style="font-size:85%;">(1994–97)</span></li> <li><a href="/wiki/Argo_(web_browser)" title="Argo (web browser)">Argo</a> <span style="font-size:85%;">(1994–97)</span></li> <li><a href="/wiki/Amaya_(web_editor)" title="Amaya (web editor)">Amaya</a> <span style="font-size:85%;">(browser/editor, 1996–2012)</span></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Conferences</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/International_World_Wide_Web_Conference" class="mw-redirect" title="International World Wide Web Conference">International World Wide Web Conference</a> (IW3C) <ul><li><a href="/wiki/International_World_Wide_Web_Conferences_Steering_Committee" class="mw-redirect" title="International World Wide Web Conferences Steering Committee">Steering Committee</a> (IW3C2)</li> <li><a href="/wiki/First_International_Conference_on_the_World-Wide_Web" title="First International Conference on the World-Wide Web">First conference</a> ("WWW1", 1994)</li></ul></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" 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