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diff --git a/htdocs/docs/users.html b/htdocs/docs/users.html
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+++ b/htdocs/docs/users.html
@@ -1,327 +1,380 @@
-<!--#set var="revision" value="\$Id: users.html,v 1.34 2009-09-27 18:03:53 ville Exp $"
---><!--#set var="date" value="\$Date: 2009-09-27 18:03:53 $"
+<!--#set var="revision" value="\$Id: users.html,v 1.35 2009-09-27 18:27:14 ville Exp $"
+--><!--#set var="date" value="\$Date: 2009-09-27 18:27:14 $"
 --><!--#set var="title" value="User Documentation for The W3C Markup Validation Service"
 --><!--#set var="relroot" value="../"
 --><!--#include virtual="../header.html" -->
 
 <div class="doc">
 
-<h2>User's guide for the W3C Markup Validator</h2>
+  <h2>User's guide for the W3C Markup Validator</h2>
 
-<h3 id="TableOfContents">Table of contents</h3>
+  <h3 id="TableOfContents">Table of contents</h3>
 
-    <div id="toc">
-	<ul>
-	<li><a href="#Quickstart">Quick Start</a></li>
-	<li><a href="#Introduction">Introduction</a></li>
-	<li><a href="#Calling">Calling/Linking to the Validator</a>
-	  <ul>
-	    <li><a href="#API">Calling the validator's API</a></li>
-	  </ul>  
-	</li>
-	<li><a href="#Options_Params">Validator's options and output formats</a>
-	  <ul>
-	    <li><a href="#Options">Options and Parameters</a></li>
-        <li><a href="#Output">Output Formats</a></li>
-        <li><a href="api.html#http_headers">Using HTTP headers to know validation results</a></li>
-	    <li><a href="#deprecated_options">Deprecated options</a></li>
-      </ul>
-    </li>
-	<li><a href="#Interpret">Interpreting the results</a></li>
-	<li><a href="#Installing">Installing the Markup Validator Locally</a></li>
-	</ul>
-    </div>
+  <div id="toc">
+    <ul>
+      <li><a href="#Quickstart">Quick Start</a></li>
+      <li><a href="#Introduction">Introduction</a></li>
+      <li><a href="#Calling">Calling/Linking to the Validator</a>
+        <ul>
+	  <li><a href="#API">Calling the validator's API</a></li>
+        </ul>
+      </li>
+      <li><a href="#Options_Params">Validator's options and output formats</a>
+        <ul>
+	  <li><a href="#Options">Options and Parameters</a></li>
+          <li><a href="#Output">Output Formats</a></li>
+          <li><a href="api.html#http_headers">Using HTTP headers to know
+              validation results</a></li>
+	  <li><a href="#deprecated_options">Deprecated options</a></li>
+        </ul>
+      </li>
+      <li><a href="#Interpret">Interpreting the results</a></li>
+      <li><a href="#Installing">Installing the Markup Validator Locally</a></li>
+    </ul>
+  </div>
 
-    <div id="Quickstart">
-      <h3><a id="skip" name="skip"></a>Quick Start</h3>
-      <p>
-        Just type (or Cut&amp;Paste) the URL for the page you want to validate
-        into the text field on the form and press the "Validate this page"
-        button.
-      </p>
-      <p>
-        If you have a local file you want to validate, choose the "File Upload"
-        link from the navigation menu. Select the button labeled "Browse..."
-        (or something like that, depending on your browser) and choose the file
-        you want to upload in the usual manner for your OS.
-      </p>
-      <p>
-        Alternatively, you can also copy and paste the <em>complete</em> markup
-        (including a <a href="help.html#faq-doctype">DOCTYPE declaration</a>)
-        for a document in the "direct input" box.
-      </p>
-    </div>
+  <div id="Quickstart">
+    <h3><a id="skip" name="skip"></a>Quick Start</h3>
+    <p>
+      Just type (or Cut&amp;Paste) the URL for the page you want to validate
+      into the text field on the form and press the "Validate this page"
+      button.
+    </p>
+    <p>
+      If you have a local file you want to validate, choose the "File Upload"
+      link from the navigation menu. Select the button labeled "Browse..." (or
+      something like that, depending on your browser) and choose the file you
+      want to upload in the usual manner for your OS.
+    </p>
+    <p>
+      Alternatively, you can also copy and paste the <em>complete</em> markup
+      (including a <a href="help.html#faq-doctype">DOCTYPE declaration</a>) for
+      a document in the "direct input" box.
+    </p>
+  </div>
 
-    <div id="Introduction" class="stb">
-      <h3>Introduction</h3>
-      <p>
-        The W3C Markup Validation Service is a web gateway to a well known SGML
-        parser called SP. SP will take your HTML and compare it to a set of
-        objective syntax rules called a "DTD", a Document Type Definition. This
-        way you can be sure your HTML is really valid and not just that it
-        conforms to some random programmer's idea of "nice" HTML. Note that
-        valid HTML does not guarantee that your pages will work OK in all
-        browsers. Most of them are severely broken and you may need to find
-        alternate ways of achieving your goal.
-      </p>
-      <p>
-        When you send an URL to the W3C Markup Validation Service, it will fetch
-        that URL and feed it to the SGML parser. If you upload a file it'll get
-        fed directly into the SGML parser. We then take the output from the
-        SGML parser and format it nicely as HTML and send it back to your web
-        browser. 
-      </p>
-      <p>
-        The W3C Markup Validation Service is not generating the error messages 
-        - they are all generated by the underlying Parser -
-        but it is appending short explanations and suggested fixes for each error.
-        We provide a <a href="../feedback.html#errormsg">feedback channel</a> for 
-        users to suggest better explanations and more accurate solutions.
-      </p>
-    </div>
+  <div id="Introduction" class="stb">
+    <h3>Introduction</h3>
+    <p>
+      The W3C Markup Validation Service is a web gateway to a well known SGML
+      parser called SP. SP will take your HTML and compare it to a set of
+      objective syntax rules called a "DTD", a Document Type Definition. This
+      way you can be sure your HTML is really valid and not just that it
+      conforms to some random programmer's idea of "nice" HTML. Note that valid
+      HTML does not guarantee that your pages will work OK in all browsers.
+      Most of them are severely broken and you may need to find alternate ways
+      of achieving your goal.
+    </p>
+    <p>
+      When you send an URL to the W3C Markup Validation Service, it will fetch
+      that URL and feed it to the SGML parser. If you upload a file it'll get
+      fed directly into the SGML parser. We then take the output from the SGML
+      parser and format it nicely as HTML and send it back to your web browser.
+    </p>
+    <p>
+      The W3C Markup Validation Service is not generating the error messages -
+      they are all generated by the underlying Parser - but it is appending
+      short explanations and suggested fixes for each error. We provide a
+      <a href="../feedback.html#errormsg">feedback channel</a> for users to
+      suggest better explanations and more accurate solutions.
+    </p>
+  </div>
 
-    <div id="Calling" class="stb">
-      <h3>Calling/Linking to the Validator</h3>
-      <p>
-        You can link directly to the Validator home page, or you can call the
-        Validator CGI program. The home page is &lt;<a
-          href="http://validator.w3.org/">http://validator.w3.org/</a>&gt; at
-        the moment (and for the foreseeable future) and the CGI program can be
-        reached at &lt;<a
-        href="http://validator.w3.org/check">http://validator.w3.org/check</a>&gt;.
-      </p>
-      <p>
-        If you call the CGI program with extra path info matching "/referer"
-        (i.e. &lt;<a href="http://validator.w3.org/check/referer">http://validator.w3.org/check/referer</a>&gt;)
-        it will fetch the referring document and validate that. This means that
-        if you embed a link to that URL in your pages, following on that link
-        will send you the validation results for that page.
-      </p>
-      <p>
-        You can also link to the validation results for a specific page. You do
-        this by giving "check" an "uri" parameter pointing at the page you want
-        to validate. For example &lt;<a href="http://validator.w3.org/check?uri=http://www.example.com/">http://validator.w3.org/check?uri=http://www.example.com/</a>&gt;
-        will validate the www.example.com home page.
-      </p>
-      <p>
-        The various options are listed below in the section
-        "<a href="#Options">Options and Parameters</a>" in parenthesis after
-        the longname. To add options to your links directly, append the options
-        separated by a semicolon. For example
-        &lt;<a href="http://validator.w3.org/check?uri=http://www.example.com/;ss=1;outline=1">http://validator.w3.org/check?uri=http://www.example.com/;ss=1;outline=1</a>&gt;
-        will validate the example.com home page with "Show Source", and
-        "Outline" on, but "Verbose" off.
-      </p>
-      <p>
-        You may also see these separated by ampersands, but this usage is
-        deprecated and support may be removed at some time in the future.
-      </p>
-      <h4 id="API">Calling the validator's API</h4>
-      <p>The Validator can also be called by programs through its <a href="api.html">API</a>. See full documentation for details.</p>
-    </div>
+  <div id="Calling" class="stb">
+    <h3>Calling/Linking to the Validator</h3>
+    <p>
+      You can link directly to the Validator home page, or you can call the
+      Validator CGI program. The home page is
+      &lt;<a href="http://validator.w3.org/">http://validator.w3.org/</a>&gt;
+      at the moment (and for the foreseeable future) and the CGI program can be
+      reached at
+      &lt;<a href="http://validator.w3.org/check">http://validator.w3.org/check</a>&gt;.
+    </p>
+    <p>
+      If you call the CGI program with extra path info matching "/referer"
+      (i.e. &lt;<a href="http://validator.w3.org/check/referer">http://validator.w3.org/check/referer</a>&gt;)
+      it will fetch the referring document and validate that. This means that
+      if you embed a link to that URL in your pages, following on that link
+      will send you the validation results for that page.
+    </p>
+    <p>
+      You can also link to the validation results for a specific page. You do
+      this by giving "check" an "uri" parameter pointing at the page you want
+      to validate. For example
+      &lt;<a href="http://validator.w3.org/check?uri=http://www.example.com/">http://validator.w3.org/check?uri=http://www.example.com/</a>&gt;
+      will validate the www.example.com home page.
+    </p>
+    <p>
+      The various options are listed below in the section
+      "<a href="#Options">Options and Parameters</a>" in parenthesis after the
+      long name. To add options to your links directly, append the options
+      separated by a semicolon. For example
+      &lt;<a href="http://validator.w3.org/check?uri=http://www.example.com/;ss=1;outline=1">http://validator.w3.org/check?uri=http://www.example.com/;ss=1;outline=1</a>&gt;
+      will validate the example.com home page with "Show Source", and "Outline"
+      on, but "Verbose" off.
+    </p>
+    <p>
+      You may also see these separated by ampersands, but this usage is
+      deprecated and support may be removed at some time in the future.
+    </p>
 
+    <h4 id="API">Calling the validator's API</h4>
+    <p>
+      The Validator can also be called by programs through its
+      <a href="api.html">API</a>. See full documentation for details.
+    </p>
+  </div>
 
-    <div id="Options_Params" class="stb">
-      <h3>Options and output formats</h3>
-      <h4 id="Options">Options and Parameters</h4>
-      <p>
-        In addition to the text field where you enter an URL -- or the file
-        selection field if you are uploading files -- there are a few
-        checkboxes that alter the behaviour of the validator.</p>
-      <p>
-	 These options are:
-      </p>
-
-      <dl>
-	<dt><a id="option-charset" name="option-charset"></a>Encoding</dt>
-	<dd>
-	  <p>This allows you to <strong>override</strong> the character encoding
-	  information about your document. You may use this option for test 
-	  purposes, but you will eventually have to serve your document with the
-	  correct character encoding, or the validator will <a href="help#faq-charset">complain</a> 
-	  about it and you document will not be valid.</p>
-	</dd>
-	<dt><a id="option-fbc" name="option-fbc"></a>Use Fallback instead of Override (Encoding) (<code>fbc</code>)</dt>
-	<dd>
-	  <p>Uses the <a href="#option-charset">character encoding override</a> mechanism
-	  described above, but only does it as a fall back mechanism if the actual document
-	  is not served with character encoding information. Think of this as a gentler 
-	  override mechanism.</p>
-	</dd>
-	<dt><a id="option-doctype" name="option-doctype"></a>Document Type (Doctype) (<code>doctype</code>)</dt>
-	<dd>
-	  <p>This allows you to <strong>override</strong> the DOCTYPE declaration for you
-	  document. You may use this option for test 
-          purposes, but you will eventually have to serve your document with the
-          correct DOCTYPE declaration, or the validator will <a href="help#faq-doctype">complain</a>
-          about it and you document will not be valid.</p>
-	</dd>
-	<dt><a id="option-fbd" name="option-fbd"></a>Use Fallback instead of Override (Type) (<code>fbd</code>)</dt>
-        <dd>
-          <p>Uses the <a href="#option-doctype">Doctype override</a> mechanism
-          described above, but only does it as a fall back mechanism if the actual document
-          does not have a Doctype declaration. Think of this as a gentler override mechanism.</p>
-        </dd>
+  <div id="Options_Params" class="stb">
+    <h3>Options and output formats</h3>
+    <h4 id="Options">Options and Parameters</h4>
+    <p>
+      In addition to the text field where you enter an URL -- or the file
+      selection field if you are uploading files -- there are a few checkboxes
+      that alter the behaviour of the validator.</p>
+    <p>
+      These options are:
+    </p>
 
+    <dl>
+      <dt><a id="option-charset" name="option-charset"></a>Encoding</dt>
+      <dd>
+        <p>This allows you to <strong>override</strong> the character encoding
+	  information about your document. You may use this option for test
+	  purposes, but you will eventually have to serve your document with
+          the correct character encoding, or the validator will
+          <a href="help#faq-charset">complain</a> about it and you document
+          will not be valid.</p>
+      </dd>
+      <dt><a id="option-fbc" name="option-fbc"></a>Use Fallback instead of
+        Override (Encoding) (<code>fbc</code>)</dt>
+      <dd>
+        <p>Uses the <a href="#option-charset">character encoding override</a>
+          mechanism described above, but only does it as a fall back mechanism
+          if the actual document is not served with character encoding
+          information. Think of this as a gentler override mechanism.
+        </p>
+      </dd>
+      <dt><a id="option-doctype" name="option-doctype"></a>Document Type
+        (Doctype) (<code>doctype</code>)</dt>
+      <dd>
+        <p>
+          This allows you to <strong>override</strong> the DOCTYPE declaration
+          for your document. You may use this option for test purposes, but you
+          will eventually have to serve your document with the correct DOCTYPE
+          declaration, or the validator will
+          <a href="help#faq-doctype">complain</a> about it and you document
+          will not be valid.
+        </p>
+      </dd>
+      <dt><a id="option-fbd" name="option-fbd"></a>Use Fallback instead of
+        Override (Type) (<code>fbd</code>)</dt>
+      <dd>
+        <p>
+          Uses the <a href="#option-doctype">Doctype override</a> mechanism
+          described above, but only does it as a fall back mechanism if the
+          actual document does not have a Doctype declaration. Think of this as
+          a gentler override mechanism.
+        </p>
+      </dd>
 
-        <dt><a id="option-ss" name="option-ss"></a>Show source input (<code>ss</code>)</dt>
-        <dd>
-          <p>Displays the HTML source of the document you validated and links
-          error messages directly to lines in this output. Makes it easy to
-          see what's wrong.</p>
-        </dd>
-        <dt><a id="option-outline" name="option-outline"></a>Show an outline of this document (<code>outline</code>)</dt>
-        <dd>
-          <p>Will generate an outline of your document from the H1 - H6 elements.
+      <dt><a id="option-ss" name="option-ss"></a>Show source input
+        (<code>ss</code>)</dt>
+      <dd>
+        <p>
+          Displays the HTML source of the document you validated and links
+          error messages directly to lines in this output. Makes it easy to see
+          what's wrong.
+        </p>
+      </dd>
+      <dt><a id="option-outline" name="option-outline"></a>Show an outline of
+        this document (<code>outline</code>)</dt>
+      <dd>
+        <p>
+          Will generate an outline of your document from the H1 - H6 elements.
           For a properly formed document, this will be a nicely nested tree
           structure. The visualization of your document's structure makes it
-          easier to see where you've skipped a heading.</p>
-          <p>If you want to examine the semantic structure of your documents, beyond the outline, try the
-            <a href="http://www.w3.org/2003/12/semantic-extractor.html">Semantic data extractor</a>.
-          </p>
-          
-        </dd>
-
-	<dt><a id="option-no200" name="option-no200"></a>Validate error pages (<code>No200</code>)</dt>
-	<dd>
-	  <p>The Markup Validator will usually tell you if the page you tried to validate
-	  could not be retrieved (for example, if the server gave a "404 not found" message.
-	  In some circumstances you may want to be able to validate the error page sent by 
-	  the server. This is the option to use then.</p>
-	</dd>
-	<dt><a id="option-verbose" name="option-verbose"></a>Verbose Output (<code>verbose</code>)</dt>
-	<dd>
-	  <p>This option triggers verbose output. Verbose output adds more explanations 
-          and suggestions to the validation results, and gives more information on the 
-          resource validated. This makes it a useful option if you prefer to be given 
-          as much help as possible; if you prefer more concise reports, leave this option
-          unset.</p>
-	</dd>
-	<dt id="option-accept">For Content-Negotiated resources, set a specific <code>Accept</code> Header (<code>accept</code>)</dt>
-	<dd>
-	  <p>This option (<em>experimental, as of 0.8.2</em>) is useful if your Web server 
-	  is set up to use format negotiation, serving different
-	  content based on the preferred/accepted media types of the user-agent. The validator
-	  can then emulate different HTTP <code>Accept</code> behaviors.</p>
-	  <p>For example, append "<code>accept=application%2Fxhtml%2Bxml%2C*</code>" and the validator
-	    will send the HTTP Header "<code>Accept: application/xhtml+xml,*</code>".</p>
-	</dd>
-	<dt id="option-accept-language">For Content-Negotiated resources, set a specific <code>Accept-Language</code> Header (<code>accept-language</code>)</dt>
-	<dd>
-	  <p>This option (<em>experimental, as of 0.8.2</em>) is useful if your Web server 
-	  is set up to use language negotiation, serving content in different languages
-	   based on the preferred/accepted language setup of the user-agent. The validator
-	  can then emulate different HTTP <code>Accept-Language</code> behaviors.</p>
-	  <p>For example, append "<code>accept-language=ja%2Cfr</code>" and the validator
-	    will send the HTTP Header "<code>Accept-Language: ja,fr</code>".</p>
-	</dd>
-	<dt id="option-accept-charset">Set a specific <code>Accept-Charset</code> Header (<code>accept-charset</code>)</dt>
-	<dd>
-	  <p>This option (<em>experimental, as of 0.8.3</em>) makes the validator send 
-	  a <code>Accept-Charset</code> HTTP header, specifying the character encodings 
-	  which it will accept from server. This option is mainly used to interface the Markup
-	  Validator for <a href="http://www.w3.org/TR/mobileOK-basic10-tests/#http_request">Mobile Web Best Practices</a>
-	  checking.</p>
-	</dd>
-	<dt id="option-user-agent">Set a specific <code>User-Agent</code> Header (<code>user-agent</code>)</dt>
-	<dd>
-	  <p>This option (<em>experimental, as of 0.8.3</em>) makes the validator send 
-	  a custom <code>User-Agent</code> HTTP header instead of the usual <code>W3C_Validator/xx.xxxx</code>.
-	  If the value of this parameter is <code>mobileok</code>, the validator will output a <code>User-Agent</code>
-	  string as defined by the <a href="http://www.w3.org/TR/mobileOK-basic10-tests/#http_request">Mobile Web Best Practices</a>
-	  spec.</p>
-	</dd>
-      </dl>
-      <h4 id="Output">Output Options</h4>
-      <p>
-        In addition to the HTML output intended for human consumption in a
-        browser, the Validator has some experimental features to generate
-        machine parseable output in a few different forms. To enable these
-        output options, append "<code>;output=&lt;option&gt;</code>" to the
-        URL of the Validation results (an interface for these options will be
-        provided when they exit the beta stage).
-      </p>
-      <dl>
-        <dt id="output-soap12">Web Service API (<code>output=soap12</code>)</dt>
-        <dd>
-          Using the SOAP1.2 language over HTTP, this defines a web service with
-          an output similar to the API for the W3C CSS validator and Feed
-          Validator. The <a href="api">Full documentation</a> for this API is
-          available. This API is <em>still under development</em>, and subject
-          to change.
-        </dd>
-        <dt id="output-earl">EARL/RDF (<code>output=earl</code>)</dt>
-        <dd>
-          Produces output in the EARL RDF syntax.
-  	  <em>This output may change or be removed in the future</em>.
-        </dd>
-  	<dt id="output-n3">Notation3 (<code>output=n3</code>)</dt>
-  	<dd>
-          Produces output in the Notation3 RDF syntax. 
-  	  <em>This output may change or be removed in the future</em>.
-        </dd>
-	<dt id="output-json">JSON (<code>output=json</code>)</dt>
-	<dd>Produces output using a JSON (JavaScript Object Notation)
-          formatting equivalent to the
-          <a href="http://wiki.whatwg.org/wiki/Validator.nu_JSON_Output">JSON
-            output for validator.nu</a>.
-        </dd> 
-  	<dt id="output-xml">XML (<code>output=xml</code>)</dt>
-  	<dd>
-          This output option has been deprecated, and will be removed from
-          future versions of the validator.
-        </dd>
-      </dl>
- 
-    <h4 id="deprecated_options">Deprecated options</h4>
-    <p>A number of options once available  have been deprecated and are not available any more.
-        This includes the <em>Show parse tree</em>  
-          and <em>exclude attributes from the parse tree</em>, as well as <em>Show ESIS</em> 
-          and <em>Show raw errors</em>.
+          easier to see where you've skipped a heading.
+        </p>
+        <p>
+          If you want to examine the semantic structure of your documents,
+          beyond the outline, try the
+          <a href="http://www.w3.org/2003/12/semantic-extractor.html">Semantic
+            data extractor</a>.
         </p>
-    </div>
+      </dd>
+      <dt><a id="option-no200" name="option-no200"></a>Validate error pages
+        (<code>No200</code>)</dt>
+      <dd>
+        <p>
+          The Markup Validator will usually tell you if the page you tried to
+          validate could not be retrieved (for example, if the server gave a
+          "404 not found" message. In some circumstances you may want to be
+          able to validate the error page sent by the server. This is the
+          option to use then.
+        </p>
+      </dd>
+      <dt><a id="option-verbose" name="option-verbose"></a>Verbose Output
+        (<code>verbose</code>)</dt>
+      <dd>
+        <p>
+          This option triggers verbose output. Verbose output adds more
+          explanations and suggestions to the validation results, and gives
+          more information on the resource validated. This makes it a useful
+          option if you prefer to be given as much help as possible; if you
+          prefer more concise reports, leave this option unset.
+        </p>
+      </dd>
+      <dt id="option-accept">For Content-Negotiated resources, set a specific
+        <code>Accept</code> Header (<code>accept</code>)</dt>
+      <dd>
+        <p>
+          This option (<em>experimental, as of 0.8.2</em>) is useful if your
+          Web server is set up to use format negotiation, serving different
+          content based on the preferred/accepted media types of the user
+          agent. The validator can then emulate different HTTP
+          <code>Accept</code> behaviors.
+        </p>
+        <p>
+          For example, append
+          "<code>accept=application%2Fxhtml%2Bxml%2C*</code>" and the validator
+          will send the HTTP Header
+          "<code>Accept: application/xhtml+xml,*</code>".
+        </p>
+      </dd>
+      <dt id="option-accept-language">For Content-Negotiated resources, set a
+        specific <code>Accept-Language</code> Header (<code>accept-language</code>)</dt>
+      <dd>
+        <p>
+          This option (<em>experimental, as of 0.8.2</em>) is useful if your
+          Web server is set up to use language negotiation, serving content in
+          different languages based on the preferred/accepted language setup of
+          the user agent. The validator can then emulate different HTTP
+          <code>Accept-Language</code> behaviors.
+        </p>
+        <p>
+          For example, append "<code>accept-language=ja%2Cfr</code>" and the
+          validator will send the HTTP Header
+          "<code>Accept-Language: ja,fr</code>".
+        </p>
+      </dd>
+      <dt id="option-accept-charset">Set a specific <code>Accept-Charset</code>
+        Header (<code>accept-charset</code>)</dt>
+      <dd>
+        <p>
+          This option (<em>experimental, as of 0.8.3</em>) makes the validator
+          send an <code>Accept-Charset</code> HTTP header, specifying the
+          character encodings which it will accept from server. This option is
+          mainly used to interface the Markup Validator for
+          <a href="http://www.w3.org/TR/mobileOK-basic10-tests/#http_request">Mobile
+            Web Best Practices</a> checking.</p>
+      </dd>
+      <dt id="option-user-agent">Set a specific <code>User-Agent</code> Header
+        (<code>user-agent</code>)</dt>
+      <dd>
+        <p>
+          This option (<em>experimental, as of 0.8.3</em>) makes the validator
+          send a custom <code>User-Agent</code> HTTP header instead of the
+          usual <code>W3C_Validator/xx.xxxx</code>. If the value of this
+          parameter is <code>mobileok</code>, the validator will output a
+          <code>User-Agent</code> string as defined by the
+          <a href="http://www.w3.org/TR/mobileOK-basic10-tests/#http_request">Mobile
+            Web Best Practices</a> spec.</p>
+      </dd>
+    </dl>
 
+    <h4 id="Output">Output Options</h4>
+    <p>
+      In addition to the HTML output intended for human consumption in a
+      browser, the Validator has some experimental features to generate machine
+      parseable output in a few different forms. To enable these output
+      options, append "<code>;output=&lt;option&gt;</code>" to the URL of the
+      validation results (an interface for these options will be provided when
+      they exit the beta stage).
+    </p>
+    <dl>
+      <dt id="output-soap12">Web Service API (<code>output=soap12</code>)</dt>
+      <dd>
+        Using the SOAP1.2 language over HTTP, this defines a web service with
+        an output similar to the API for the W3C CSS validator and Feed
+        Validator. The <a href="api">Full documentation</a> for this API is
+        available. This API is <em>still under development</em>, and subject to
+        change.
+      </dd>
+      <dt id="output-earl">EARL/RDF (<code>output=earl</code>)</dt>
+      <dd>
+        Produces output in the EARL RDF syntax.
+        <em>This output may change or be removed in the future</em>.
+      </dd>
+      <dt id="output-n3">Notation3 (<code>output=n3</code>)</dt>
+      <dd>
+        Produces output in the Notation3 RDF syntax.
+        <em>This output may change or be removed in the future</em>.
+      </dd>
+      <dt id="output-json">JSON (<code>output=json</code>)</dt>
+      <dd>
+        Produces output using a JSON (JavaScript Object Notation) formatting
+        equivalent to the
+        <a href="http://wiki.whatwg.org/wiki/Validator.nu_JSON_Output">JSON
+          output for validator.nu</a>.
+      </dd>
+      <dt id="output-xml">XML (<code>output=xml</code>)</dt>
+      <dd>
+        This output option has been deprecated, and will be removed from future
+        versions of the validator.
+      </dd>
+    </dl>
+
+    <h4 id="deprecated_options">Deprecated options</h4>
+    <p>
+      A number of options once available  have been deprecated and are not
+      available any more. These includee the <em>Show parse tree</em> and
+      <em>exclude attributes from the parse tree</em>, as well as <em>Show
+        ESIS</em> and <em>Show raw errors</em> options.
+    </p>
+  </div>
 
-    <div id="Interpret" class="stb">
-      <h3>Interpreting the results</h3>
-      <p>
-        In spite of our efforts,  interpreting the Markup Validator's error messages 
-	isn't quite what you'd call easy. The error messages are generated in the 
-	context of a full SGML environment which demands a somewhat higher level 
-	of technical detail than your average HTML document. We have set up a page 
-	listing <a href="errors.html">errors and their explanation</a>, which should
-	help you find out what meaning lies behind the cryptic messages, and fix
-	your markup.
-      </p>
-      <p>
-	We're working on ways to make the error messages more friendly, but for now,
-	if the <a href="errors.html">errors explanation page</a> doesn't work for you,
-        or if you wish to suggest a better explanation, our
-        <a href="../feedback.html#errormsg">feedback page</a> will help you send your 
-        ideas to our public mailing-list. This will have
-        the added benefit of letting us know which error messages are causing
-        the most trouble so we can fix those first. Please be as specific as
-        possible and include the <em>exact</em> error message and, preferably, an URL
-        we can validate to see for ourselves.
-      </p>
-    </div>
 
+  <div id="Interpret" class="stb">
+    <h3>Interpreting the results</h3>
+    <p>
+      In spite of our efforts,  interpreting the Markup Validator's error
+      messages isn't quite what you'd call easy. The error messages are
+      generated in the context of a full SGML environment which demands a
+      somewhat higher level of technical detail than your average HTML
+      document. We have set up a page listing <a href="errors.html">errors and
+        their explanations</a>, which should help you find out what meaning
+      lies behind the cryptic messages, and fix your markup.
+    </p>
+    <p>
+      We're working on ways to make the error messages more friendly, but for
+      now, if the <a href="errors.html">errors explanation page</a> doesn't
+      work for you, or if you wish to suggest a better explanation, our
+      <a href="../feedback.html#errormsg">feedback page</a> will help you send
+      your ideas to our public mailing list. This will have the added benefit
+      of letting us know which error messages are causing the most trouble so
+      we can fix those first. Please be as specific as possible and include the
+      <em>exact</em> error message and, preferably, a URL we can validate to
+      see for ourselves.
+    </p>
+  </div>
 
-    <div id="Installing" class="stb">
-      <h3>Installing a local Validator</h3>
-      <p>
-        You can download the Validator to run on your own system. For Web design departments
-	or agencies it can be a very good idea, saving time and allowing you to not send 
-	documents under work or confidential pages over the wire,  but it is a complex operation, 
-	and is not recommended for average users, for which the free online service at W3C
-	should suffice.
-      </p>
-      <p>
-	We have created a simple <a href="install.html">Installation manual</a>, which, along with 
-	the <a href="devel.html">Developer's information</a>, should help you install a local instance
-	of the Markup Validator in your own network easily.
-      </p>
-    </div>
+  <div id="Installing" class="stb">
+    <h3>Installing a local Validator</h3>
+    <p>
+      You can download the Validator to run on your own system. For Web design
+      departments or agencies it can be a very good idea, saving time and
+      allowing you to not send documents under work or confidential pages over
+      the wire, but it is a complex operation, and is not recommended for
+      average users, for which the free online service at W3C should suffice.
+    </p>
+    <p>
+      We have created a simple <a href="install.html">Installation manual</a>,
+      which, along with the <a href="devel.html">Developer's information</a>,
+      should help you install a local instance of the Markup Validator in your
+      own network easily.
+    </p>
+  </div>
 </div>
 
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