character-set.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- $Id: character-set.xml,v 1.129 2015/09/07 08:37:08 dcarlis Exp $ -->
<!DOCTYPE spec [<!ENTITY date "20170807">]>
<spec w3c-doctype="rec">
<header>
<title>XML Entity Definitions for Characters (3rd Edition)</title>
<w3c-designation>xml-entity-names-&date;</w3c-designation>
<w3c-doctype>W3C Recommendation</w3c-doctype>
<pubdate><day>07</day> <month>August</month> <year>2017</year></pubdate>
<publoc>
<!--<loc href="http://www.w3.org/TR/2014/REC-xml-entity-names-&date;/">http://www.w3.org/TR/2014/REC-xml-entity-names-&date;/</loc>-->
<!--
<loc href="https://www.w3.org/2003/entities/2007doc/">https://www.w3.org/2003/entities/2007doc/</loc>
-->
<loc href="https://www.w3.org/TR/2017/REC-xml-entity-names-&date;/">https://www.w3.org/TR/2017/REC-xml-entity-names-&date;/</loc>
</publoc>
<latestloc>
 <!--
     <loc href="https://www.w3.org/TR/xml-entity-names/">https://www.w3.org/TR/xml-entity-names/</loc>
 -->
   <loc href="https://www.w3.org/TR/2017/WD-xml-entity-names-20170807/">https://www.w3.org/TR/2017/REC-xml-entity-names-20170807/</loc>
</latestloc>
<prevlocs>
  <loc href="https://www.w3.org/TR/2014/REC-xml-entity-names-20140410/">https://www.w3.org/TR/2014/REC-xml-entity-names-20140410/</loc><!--
  <loc href="https://www.w3.org/TR/2014/PER-xml-entity-names-20140211/">https://www.w3.org/TR/2014/PER-xml-entity-names-20140211/</loc>
  <loc href="https://www.w3.org/TR/2010/REC-xml-entity-names-20100401/">https://www.w3.org/TR/2010/REC-xml-entity-names-20100401/</loc>
-->
<!--
  <loc href="https://www.w3.org/TR/2010/PR-xml-entity-names-20100211/">https://www.w3.org/TR/2010/PR-xml-entity-names-20100211/</loc>
  <loc href="https://www.w3.org/TR/2009/WD-xml-entity-names-20091117/">https://www.w3.org/TR/2009/WD-xml-entity-names-20091117/</loc>
  <loc href="https://www.w3.org/TR/2007/WD-xml-entity-names-20071214/">https://www.w3.org/TR/2007/WD-xml-entity-names-20071214/</loc>
-->
</prevlocs>
<edlocs>
  <loc href="https://www.w3.org/2003/entities/2007doc/">https://www.w3.org/2003/entities/2007doc/</loc>
</edlocs>
<authlist>
<author>
<name>David Carlisle</name>
<affiliation>NAG</affiliation>
</author>
<author>
<name>Patrick Ion</name>
<affiliation>Mathematical Reviews, American Mathematical Society</affiliation>
</author>
</authlist>
<errataloc href="errata.html"/>
<translationloc href="https://www.w3.org/2005/11/Translations/Query?titleMatch=XML+Entity+definitions+for+Characters"/>

<status id="status">


<p><emph> This section describes the status of this document at the time
of its publication. Other documents may supersede this document. A
list of current W3C publications and the latest revision of this
technical report can be found in the <loc
href="https://www.w3.org/TR/">W3C technical reports index</loc> at
https://www.w3.org/TR/.</emph>
</p> 
<!--
<p>Publication as a Proposed Edited Recommendation does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.</p>
-->

<!-- rec version -->
<p>This document has been reviewed by W3C Members, by software
developers, and by other W3C groups and interested parties, and is
endorsed by the Director as a W3C Recommendation. It is a stable
document and may be used as reference material or cited from another
document. W3C's role in making the Recommendation is to draw attention
to the specification and to promote its widespread deployment. This
enhances the functionality and interoperability of the Web.</p>


<!-- WD version
<p>Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.</p>
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<p>This third edition is based on Unicode <phrase role="unicode"/> and
incorporates changes to Unicode since Unicode 5.2 and 6.3,
on which the first and second editions of this document were based. Note these updates only affect
the non normative descriptions of the Unicode blocks. There are no changes to the Normative entity definitions.
It also has been updated and restructured slightly to note that <bibref ref="HTML5"/> now uses these definitions.
and to more clearly highlight that the HTML-MathML entity set should be used in preference to the older ISO sets
that are also defined in this document.</p>
<p>
This document was produced by the 
<loc href="https://www.w3.org/Math/">W3C Math Working Group</loc>
as a Recommendation and as part of the W3C 
<loc href="https://www.w3.org/Math/Activity">Math Activity</loc>.
The goals of the W3C Math Working Group are discussed in the 
<loc href="https://www.w3.org/Math/Documents/Charter2006.html"> W3C Math WG Charter</loc>.  
The authors of this document are W3C Math Working Group members.
</p>

<!--
<p>
W3C asks members of the Advisory Committee to review this document
and fill in the <loc href="https://www.w3.org/2002/09/wbs/33280/">
review form.</loc> The deadline for this is 11 March 2014. The document did not
undergo Candidate Recommendation review, because no software
is needed to implement the specification other than a standard XML parser and there are no changes to
the normative content of this Recommendation, the entity definitions, since the first edition Recommendation.
</p>
-->
<p>
Comments should be sent to the 
<loc href="mailto:www-math@w3.org">Public W3C Math mailing list</loc>
(<loc href="https://lists.w3.org/Archives/Public/www-math/">list archives</loc>;
see also <loc href="https://www.w3.org/Mail/Request">instructions</loc>).
When sending an e-mail comment on the XML Entity Definitions for Characters, please 
put the text &#x201C;XML-Entities&#x201D; in the subject line, preferably like this: 
&#x201C;[XML-Entities] &#x2026;summary of comment &#x201D;.
<phrase diff="add">Alternatively, report  an issue at this specification's <loc href="https://github.com/w3c/xml-entities">GitHub repository</loc>.</phrase>
</p>

<p>This document is governed by the <loc id="w3c_process_revision" href="https://www.w3.org/2017/Process-20170301/">1 March 2017 W3C Process Document</loc>. </p>

<p>This  document was produced by a group operating under the 
<loc href="https://www.w3.org/Consortium/Patent-Policy-20040205/">5 February 2004 W3C Patent Policy</loc>. 
W3C maintains a 
<loc role="disclosure" href="https://www.w3.org/2004/01/pp-impl/35549/status">public list of any patent disclosures</loc> made in connection with 
the deliverables of the group; that page also includes instructions 
for disclosing a patent. An individual who has actual knowledge of 
a patent which the individual believes contains 
<loc href="https://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential Claim(s)</loc> 
must disclose the information in accordance with 
<loc href="https://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section 6 of the W3C Patent Policy</loc>. 
</p>
<p> Appendix <specref ref="changes"/>  details the changes since earlier versions of this document.</p>

</status>
<abstract id="abstract">
<p>
This document defines several sets of names, so that to each name is assigned 
a Unicode character or sequence of characters.
Each of these sets is expressed as a file of XML entity declarations.
</p>
</abstract>

<langusage>
<language id="en">English</language>
</langusage>

<revisiondesc>
<p>
First draft, derived from the MathML2 sources.
</p>
<p>
Second draft, incorporating comments from Karl Tomlinson, 
Ian Hickson and others.
</p>
<p>
Final Last Call draft, incorporating new comments from many and 
ensuring that the listings are fully up-to-date with W3C and 
Unicode development.
</p>
<p>
Proposed Recommendation form incorporating editorial changes from the
Director's meeting at which the decision to advance the status
was reached and a couple of tiny late corrections.</p>
<p>2nd edition version incorporating the Arabic Mathematical symbols block.</p>
</revisiondesc>

</header>
<body>

<div1 id="chars_intro"><head>Introduction</head>


<p>
Notation and symbols have proved very important for human communication,
especially in scientific documents. Mathematics has 
grown in part because its notation continually changes toward being succinct
and suggestive. There have been many new signs
<phrase>developed</phrase> for use in mathematical notation, and
mathematicians have not held back from making use of many symbols
originally <phrase>introduced</phrase> elsewhere. The result is that
science in general, and particularly mathematics, makes use of 
a very large collection of symbols.  It is
difficult to write science fluently if these characters are not
available for use. It is difficult to read science if
corresponding glyphs are not available for presentation on specific
display devices. In the majority of cases it is preferable to store
characters directly as Unicode character data or as XML numeric
character references.
</p>
<p>However, in some environments it is more
convenient to use the ASCII input mechanism provided by XML entity
references. Many entity names are in common use, and this 
specification aims to provide standard mappings to Unicode for each of
these names. It introduces no names that have not already been used in
earlier specifications. Note that these names are short mnemonic names 
designed for input methods such as XML entity references, not the longer formal names
that form part of the Unicode standard.
</p>
<p>
Specifically, the entity names in the sets
starting with the letters <quote>iso</quote> were first standardized in SGML (<bibref
ref="SGML"/>) and updated in <bibref ref="ISO9573-13-1991"/>.
The  W3C Math Working Group has been
invited to take over the maintenance and development of these sets by the
original standards committee (ISO/IEC JTC1 SC34). The sets with names
starting  <quote>mml</quote> were first standardized in 
MathML <bibref ref="MathML2"/> and those starting
with <quote>xhtml</quote> were first standardized in HTML <bibref ref="HTML4"/>.
</p>
<p>This document is the result of years of employing entity names on the Web.  There were
always a few named entities used for special characters in HTML, and many more names
used for MathML. This means that this document can be
viewed as an extension and final revision of Chapter 6 of the MathML 2.0 
<bibref ref="MathML2"/> recommendation.  Now it presents a completed listing harmonizing
the known uses of character entity names in XML and HTML, together with defined mappings to Unicode.
</p>
<p>Since there are so many character entity names, and the files specifying them 
are resources that may be subject to frequent lookup, a template catalog file has also been
provided.  Users are strongly encouraged to design their implementations so that 
relevant entity name tables are cached locally, since it is not expected that 
the listings provided with this specification will need changing for some long time.
</p>

</div1>

<div1 id="sets">
<head>Sets of names</head>

<div2 id="htmlmathml">
<head>The HTML MathML entity set</head>
<p>Historically the entity sets have been split into relatively small groups of related characters
however for any new document type that is being defined it is strongly recommended that the combined
<kw>htmlmathml</kw> set is used. This defines an identical set of names to the names built in to
the HTML parser (derived from the same source materials as this document see <specref ref="source"/>).</p>
<p>To incorporate the <kw>htmlmathml</kw> set into an XML DTD, a typical construct is:</p>
<eg><![CDATA[
       <!ENTITY % htmlmathml-f PUBLIC
         "-//W3C//ENTITIES HTML MathML Set//EN//XML"
         "https://www.w3.org/2003/entities/2007/htmlmathml-f.ent"
       >
       %htmlmathml-f;
]]>
</eg>
<p>
The public identifier should always be used verbatim,
The system identifier should be changed to suit local requirements.
</p>
<p>The entity set is available in two forms: </p>
<ulist>
<item><p><loc href="https://www.w3.org/2003/entities/2007/htmlmathml-f.ent">htmlmathml-f</loc> the expanded set of HTML and MathML entity definitions</p></item>
<item><p><loc href="https://www.w3.org/2003/entities/2007/htmlmathml.ent">htmlmathml</loc> the HTML and MathML entities defined via reference to the legacy entity set definitions as listed in the following section.</p></item>
</ulist>
<p>The information is also available in JSON format. The JSON arrays encode the entity names and mappings to Unicode and also a list of those entity references for which the HTML (but not XML) parser allows the trailing semicolon to be omitted. So <code>&amp;amp</code> may be used as well as <code>&amp;amp;</code> when using HTML.</p>
<ulist>
<item><p><loc href="2007/htmlmathml.json">htmlmathml.json</loc></p></item>
</ulist>
<p>An XSLT2 stylesheet is available which performs the reverse mapping, replacing Unicode characters by entity references.</p>
<ulist>
<item><p><loc href="2007/htmlmathml.xsl">htmlmathml.xsl</loc></p></item>
</ulist>
</div2>

<div2 id="legacysets">
<head>Legacy Entity sets</head>

<p>This specification defines mappings to Unicode of many sets of names
that have been defined by earlier specifications.</p>

<p>We present two tables listing all the sets combined, first in 
Unicode order and then in alphabetic order:</p>
<ulist>
<item><p>All in <loc href="2007doc/bycodes.html">Unicode order</loc></p></item>
<item><p>All in <loc href="2007doc/byalpha.html">alphabetic order</loc>.</p></item>
</ulist>
<p>Then there come tables
documenting each of the entity sets. Each set has a link to the DTD
entity declaration for the corresponding entity set, and also a link
to an XSLT2 stylesheet that will implement a reverse mapping from
characters to entity names (this is, of course, only possible for  entity names
that map to a single Unicode code point).
</p>
</div2>
</div1>

<div1 id="blocks">
<head>Unicode Character Ranges for Scientific Documents</head>
<p>
Certain characters are of particular relevance to scientific document production. The following 
tables display Unicode ranges containing the characters that are most used in mathematics.
</p>
<p>Note that each of the tables linked from this section contains 256 images and may take a 
while to load if the images have not been cached locally.</p>
</div1>


<div1 id="alphabets">
<head>Mathematical Alphanumeric Characters</head>
<p>
Many of the entities defined by this specification relate to the
mathematical alphanumeric characters contained in the letter-like
symbols block of Unicode Plane 0, or in the Mathematical Alphanumeric Symbols
block in Unicode Plane 1.  The following tables list all these symbols,
highlighting those that are not in Plane 1, and giving entity names
where appropriate.
</p>
</div1>


<div1 id="combining">
<head>Entities for Negated and Variant Characters</head>
<p>
Each of the entity definitions in a majority of the specification expands 
to a single Unicode character. The definitions that expand to a sequence of 
two or more characters are outlined in this section.
</p>

<div2 id="chars_math-negated-tables">
<head>Negated Mathematical Characters</head>

<p>
In addition to the Unicode Characters so far listed, one may use the
combining characters <phrase diff="chg">U+0338</phrase> (/), 
<phrase diff="chg">U+20D2</phrase> (|) and 
<phrase diff="chg">U+20E5</phrase> (\) to produce
negated or <phrase diff="chg">canceled</phrase> forms of 
characters. A combining character
should be placed immediately after its <quote>base</quote> character, with no
intervening markup or space, just as is the case for combining accents.
</p>

<p>
In principle, the negation characters may be applied to any Unicode
character, although fonts designed for mathematics typically have some
negated glyphs ready composed. A MathML renderer should be able to use
these pre-composed glyphs in these cases.  A compound character code
either represents a UCS character that is already available, as in the
case of <phrase diff="chg">U+003D U+0338</phrase> which amounts to 
<phrase diff="chg">U+2260</phrase>, or it does not, as is the
case for <phrase diff="chg">U+2202 U+0338</phrase>. The common cases of 
negations, <phrase diff="chg">of the latter  type</phrase>,
that have been identified are listed in the tables.</p>

<p id="cancellations"/>

<p>
Note that it is the policy of the W3C and of Unicode that if a single
character is already defined for what can be achieved with a combining
character, that character must be used instead of the decomposed form.
It is also intended that no new single characters representing what
can be done by with existing compositions will be introduced. 
<phrase diff="add">For further information on these matters see
the Unicode Standard Annex 15, Unicode Normalization Forms 
<bibref ref="Unicode15"/>, especially
the discussion of Normalization Form C.</phrase>
</p>


</div2>

<div2 id="chars_math-variant-tables"><head>Variant
Mathematical Characters</head>

<p>
Unicode attempts to avoid having several character codes for simple
font variants.  For a code point to be assigned there should be
more than a nuance in glyphs to be recorded.  To record 
variants worth noting there is a special character <phrase diff="chg">in</phrase>
Unicode 3.2, U+FE00 (VARIATION SELECTOR-1), which
acts as a postfix modifier.  However the legally allowed
combinations with this variation selector are restricted to a
list recorded as part of Unicode. The  VARIATION SELECTOR-1
character may only be applied to the characters listed here.
The resulting combination is not regarded by Unicode as a separate
character, but a variation on the base character. Unicode aware systems
may render the combination as the base if the available fonts do not
support the variant glyph shape.
</p>

<p id="variants"/>

</div2>

</div1>

</body>
<back>
  <div1 id="oddities">
    <head>Special Considerations</head>
    <div2 id="epsilon">
      <head>Epsilon</head>
      <p>Historically there has been much confusion and lack of
      agreement over variant forms for lower case epsilon.</p>
      <p>This specification uses the definitions below. Note that the
      name <kw>epsilon</kw> is used for the character used in textual
      Greek (U+03B5) and <kw>varepsilon</kw> used for the epsilon
      symbol character more commonly used in mathematics
      (U+03F5). Note that this usage is compatible with the naming of
      similar pairs of characters (for example <kw>theta</kw>,
      <kw>vartheta</kw>) but <emph>incompatible</emph> with the naming
      convention used in TeX, MathML2 and some earlier mappings of the
      ISO entity sets to Unicode.</p>
      <p id="epsilontab"/>
    </div2>
    <div2 id="phi">
      <head>Phi</head>
      <p>The situation for phi is very similar to that of epsilon,
      although with the further complication that early versions of
      Unicode had the sample glyphs for U+03C6 and U+03D5 swapped
      from the current usage, and some older fonts still in use follow
      that older convention. The definitions used in this
      specification are as listed below.</p>
      <p id="phitab"/>
    </div2>

<div2 id="chars_math-multiple-tables">
<head>Multiple Character Entities</head>
<p>
In addition to the combining and variant character combinations
listed in the previous sections,
the following table lists the remaining entity replacement texts that
consist of more than one character.
</p>

<p id="multiple"/>

<p>Unicode does not have an fj character, although the other common f ligatures 
such as fi (U+FB01) are contained in the Alphabetic Presentation Forms block.
The <kw>fjlig</kw> entity is mapped to the pair of characters <quote>fj</quote>; 
modern typesetting engines should automatically use the fj ligature for this 
combination if the font supplies such a ligature.</p>
<p>Unicode has a range of space characters (including all multiples of
1/18 em up to 6/18, except for 5/18 em) thus the <kw>ThickSpace</kw> entity is 
mapped to a pair of space characters.  An alternative would have been to use
U+2005 (1/4 em), but 1/4 em is not equal to 5/18 em, so the above definition was
chosen, despite the fact that the difference is unlikely to be visibly
noticeable at most typeset font sizes.</p>
<p>The entities <kw>race</kw> and <kw>acE</kw> denote underlined
characters for which Unicode does not have codepoints, thus combining
underline characters have been used, in a way analogous to the use of
combining strokes for negated operators.</p>
</div2>

<div2 id="chars_math-combining-tables">
<head>Entities Defined to be a Combining Character</head>
<p>
The following table lists the entity replacement texts that
consist of a combining character.
</p>

<p id="combining-start"/>

<p>For reasons explained further in <bibref ref="Charmod-norm"/>, it is
not advisable to to start the replacement text of an entity with a
combining character, as then potentially different results may be
produced depending on the order in which entity expansion and Unicode
normalisation are performed. As far as possible this specification
uses non-combining characters, however, in the cases <kw>DownBreve</kw>,
<kw>tdot</kw>, <kw>TripleDot</kw> and <kw>DotDot</kw>
Unicode only has combining forms of the accents.</p>
<p>Earlier versions of this specification defined these entities
with the replacement text starting with a space, to avoid the possibility that
the expansion of the entity combined with preceding text. However for various reasons
the entities as incorporated in HTML do not have a space here, and so the
definitions now consist just of the combining character so that HTML and XHTML
are consistent with any specifications using these definitions.</p>
</div2>

  </div1>
  <div1 id="changes">
    <head>Changes</head>
    <div2 id="changes20140410">
     <head>Changes since 2014-04-10 (Second Edition Recommendation)</head>
     <p>Reference added to the 1 March 2017 W3C Process Document.</p>
     <p>Some changes to the front matter including link to GitHub as
     required by the latest W3C publication process.</p>
     <p>Adjustments to CSS styling to match new W3C document style.</p>
      <p>Source files updated to Unicode 11.0, affecting the character tables,
      but with no changes to generated entity files or stylesheets.</p>
      <p>The source repository has been moved to github so the log is now public.</p>
      <p>As detailed in <specref ref="chars_math-combining-tables"/> <kw>DownBreve</kw>,
      <kw>tdot</kw>, <kw>TripleDot</kw> and <kw>DotDot</kw> are no longer prefixed by a space.</p>
    </div2>
    <div2 id="changes20100401">
      <head>Changes between 2010-04-01 and 2014-04-10 (First and Second Edition Recommendations)</head>
      <p>Source files updated to Unicode 6.3, affecting the character tables,
      but with no changes to generated entity files or stylesheets.</p>
      <p>Source files updated Unicode 6.1 data on Arabic math alphabets (U+1EE??). Additional tables shown in Sections 3 and 4.</p>
      <p>Section <specref ref="sets"/> reorganized to highlight the <code>htmlmathml</code> set which is used in MathML and HTML. Also link to XSL and JSON formats for the HTML MathML set.</p>
      <p>References updated: <bibref ref="MathML3"/>, <bibref ref="HTML5"/> and  <bibref ref="Unicode"/>.</p>
    </div2>
    <div2 id="changes20100211">
      <head>Changes between 2010-04-01 and 2010-02-11</head>
      <p>Several example images improved, bringing them more in line with the Unicode reference images.</p>
    </div2>
    <div2 id="changes20091117">
      <head>Changes between 2010-02-11 and 2009-11-17</head>
      <p>Various editorial improvements, including using Unicode U+1234
      notation more consistently rather than displaying the  internal
      IDs of the form U01234.</p>
      <p>The combined entities file distributed with the 2009-11-17
      draft introduced an error that if two entity names differed only
      by case, only one was included. This has been corrected.</p>
      <p>The combined entity set htmlmathml corresponding to the
      entities usable in HTML and MathML is now explicitly provided. The
      predefined set, corresponding to the entities predefined in XML
      is now documented (it was previously used internally).</p>
      <p>The entities <kw>xvee</kw> and <kw>xwedge</kw> had the correct
      Unicode assignments (U+22C1 and U+22C0) but the entity descriptions
      have been swapped, <kw>xvee</kw> is logical or and <kw>xwedge</kw> is logical and.
      This error in <bibref ref="ISO9573-13-1991"/> was reported in 1999,
      <!--<loc href="https://www.jtc1sc34.org/repository/0063.htm">-->in a Proposed Technical Corrigendum,<!--</loc>-->
      but not previously fixed. The entity files are unaffected by this change.</p>
      <p>The entity <kw>NotGreaterFullEqual</kw> which had been erroneously assigned to 
      a negated less than operator (U+2266 U+0338) has been corrected to be the negated greater than operator (U+2267 U+0338).</p>
      <p>A sample <loc href="#catalog">catalog</loc> is now provided to redirect references to the entity files to copies on the local machine rather than the W3C server.</p>
    </div2>
    <div2 id="changes20080721">
      <head>Changes between 2009-11-17 and 2008-07-21</head>
      <p>The html5-uppercase set is now documented.</p>
      <p>The entities <kw>ohm</kw> and <kw>angst</kw> have changed to U+03A9 and U+00C5 to match NFC. See 
      <loc href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=5897">w3c bugzilla entry</loc>.</p>
      <p>The entity <kw>race</kw>, which had been erroneously assigned  U+29DA,
      is now assigned the combination U+223D U+0331. (U+223D isn't
      quite the shape shown in the original ISO document which is a
      rotated S rather than a rotated tilde, but this appears to be
      the closest character in Unicode 5.2.)</p>
      <p>The entities <kw>bsolhsub</kw> and <kw>suphsol</kw> which were previously
      mapped to two-character combinations U+005C U+2282 and U+2283 U+002F
      are now mapped to the Unicode 5 characters that were added
      specifically to support these entities, U+27C8 and U+27C9.</p>
      <p>The source files have all been updated to match Unicode 5.2.</p>
      <p>The entity <kw>ThickSpace</kw> now maps to the pair
        U+205F U+200A rather than the triple U+2009 U+200A U+200A
      (4/18 + 1/18)em rather than (3/18 + 1/18 + 1/18)em.</p>
      <p>The entity <kw>UnderBar</kw> maps to the spacing character
       _ rather than the combining character U+0332.</p>
      <p>The entity <kw>OverBar</kw> maps to the spacing character
       U+203E (like the XHTML entity <kw>oline</kw>) rather than the macron character U+00AF.</p>
       <p>The entities <kw>epsiv</kw> and <kw>varepsilon</kw> are now mapped to the epsilon symbol 
       U+03F5 rather than being aliases for  the entity <kw>epsilon</kw>, U+03B5.</p>
       <p>The entities <kw>phiv</kw> and <kw>varphi</kw> are now mapped to the phi symbol U+03D5 
       rather than being aliases for  the entity <kw>phi</kw>, U+03C6.</p>
    </div2>
    <div2 id="changes20071214">
      <head>Changes between 2008-07-21 and 2007-12-14</head>
      <p>The following entity definitions have changed at this draft:</p>
      <p><kw>phi</kw>, <kw>lang</kw>, <kw>rang</kw>, 
      <kw>OverParenthesis</kw>, <kw>UnderParenthesis</kw>, 
      <kw>OverBrace</kw>, <kw>UnderBrace</kw>,
      <kw>lbbrk</kw>, <kw>rbbrk</kw>.</p>
    </div2>
  </div1>
  <div1 id="diffs">
    <head>Differences between these entities and earlier W3C DTDs</head>
    <div2 id="diff-xhtml1">
      <head>Differences from XHTML 1.0</head>
      <p>Differences between the XHTML entity definitions described here and the entity set 
      described in the <loc href="https://www.w3.org/TR/xhtml1/dtds.html">XHTML 1.0 DTD</loc>.</p>
      <glist>
	<gitem><label><kw>lang</kw> and <kw>rang</kw></label><def><p>U+27E8 and
	U+27E9; XHTML 1.0 used U+2329 and  U+232A (which have canonical
	decomposition to U+3008 and U+3009).</p></def></gitem>
      </glist>
      <note><p>The current drafts of <bibref ref="HTML5"/> use entity definitions derived from 
      this specification.</p></note>
	
    </div2>
    <div2 id="diff-mathml2">
      <head>Differences from MathML 2.0 (second edition)</head>
      <p>The differences between MathML 2 and the current entity
      definitions are listed below.</p>
      <glist>
	<gitem><label><kw>fjlig</kw></label><def><p>ISOPUB (and MathML 1) defined an fj ligature; 
   Unicode does not have a specific character and the entity was dropped from MathML2.
   It is re-instated here for maximum compatibility with <bibref ref="SGML"/>.</p></def></gitem>
	<gitem><label><kw>phi</kw></label><def><p>U+03C6 GREEK SMALL LETTER PHI 
	(the definition used in HTML4); 
	MathML2 used  U+03D5 GREEK PHI SYMBOL. </p></def></gitem>
	<gitem><label><kw>epsiv</kw>, <kw>varepsilon</kw>, <kw>phiv</kw>, 
	<kw>varphi</kw></label><def><p>these have been changed to map to the symbol character 
	(to match other uses of the var prefix such as <kw>vartheta</kw>).</p></def>
<!--
      <note><p>It is very difficult for (X)HTML
      definitions to change since HTML is so widely deployed. Many of
      the assignments in the current definitions would be different if
      it were not for HTML compatibility.  However in this case,
      perhaps this change could be made in an XHTML2/HTML5 time frame.
      Currently U+03D5 has the entity names:
      straightphi,phis. U+03C6 has the entity names phi, phgr, phiv,varphi.</p>
      <p>It is also worth noting that Unicode has changed (swapped)
      the default glyphs for U+03C6 and U+03D5 since the publication
      of HTML4. The current recommendation is to use a cursive form
      for U+03C6 (<graphic role="glyph" source="U003C6"/>), and a form
      with a straight vertical bar for  U+03D5 (<graphic role="glyph"
      source="U003D5"/>). Some newer fonts  
      use glyphs that correspond to the change made by Unicode, while a number of
      older fonts remain unchanged and hence will display the glyphs swapped
      relative to the current version of Unicode.  There is no way to guarantee
	that the intended glyph is displayed without font-specific knowledge.</p></note>
--></gitem>
	<gitem><label><kw>jmath</kw></label><def><p>U+0237; MathML 2 used U+006A (j) as
	there was no dotless j before Unicode 4.1.</p></def></gitem>
	<gitem><label><kw>trpezium</kw>, <kw>elinters</kw></label><def><p>U+23E2 and U+23E7;
	MathML 2 used U+FFFD (REPLACEMENT CHARACTER) as these characters were added at Unicode 5.0
	specifically to support these entities. </p></def></gitem>
	<gitem><label><kw>ohm</kw>, <kw>angst</kw></label><def><p>As noted above, the
	definitions of these entities have been changed so that the
	definitions use characters that are in NFC normal
	form.</p></def></gitem>
	<gitem><label><kw>bsolhsub</kw> and <kw>suphsol</kw></label><def><p> U+27C8 and
	U+27C9;
MathML2 used U+005C U+02282 and   U+2283 U+002F.</p></def></gitem>
	<gitem><label><kw>NotGreaterFullEqual</kw></label><def><p> U+2267 U+0338 ;
             MathML2 used the erroneous definition U+2266 U+0338.</p></def></gitem>
      </glist>
      <p>The following bracket  symbols have been added to the Mathematical
      symbols block in Unicode versions between 3.1 and 5.1. MathML2 used
      similar characters intended for CJK punctuation.</p>
      <glist>
	<gitem><label><kw>lang</kw>, <kw>langle</kw>, <kw>LeftAngleBracket</kw> and 
	<kw>rang</kw>, <kw>rangle</kw>, <kw>RightAngleBracket</kw></label><def><p>U+27E8 and
	U+27E9; MathML2 used U+2329 and  U+232A (which have canonical
	decomposition to U+3008 and U+3009).</p></def></gitem>
	<gitem><label><kw>Lang</kw> and <kw>Rang</kw></label><def><p>U+27EA and U+27EB;
	MathML2 used U+300A and U+300B.</p></def></gitem>
	<gitem><label><kw>lbbrk</kw> and <kw>rbbrk</kw></label><def><p>U+2772 and
	U+2773; MathML2 used U+3014 and  U+3015.</p></def></gitem>
	<gitem><label><kw>loang</kw> and <kw>roang</kw></label><def><p>U+27EC and
	U+27ED; MathML2 used U+3018 and  U+3019.</p></def></gitem>
	<gitem><label><kw>lobrk</kw> and <kw>robrk</kw></label><def><p>U+27E6 and
	U+27E7; MathML2 used U+301A and U+301B.</p></def></gitem>

	<gitem><label><kw>OverBrace</kw> and <kw>UnderBrace</kw></label><def><p>U+23DE and U+23DF; MathML2
	used U+FE37 and  U+FE38.</p></def></gitem>
	<gitem><label><kw>OverParenthesis</kw> and
	<kw>UnderParenthesis</kw></label><def><p>U+23DC and U+23DD;
	MathML2 used U+FE35 and U+FE36.</p></def></gitem>
	<gitem><label><kw>LeftDoubleBracket</kw> and
	<kw>RightDoubleBracket</kw></label><def><p>U+27E6 and U+27E7;
	MathML2 used U+301A and U+301B.</p></def></gitem>
      </glist>
      <note><p><bibref ref="MathML3"/> uses the entity sets defined by this specification.</p></note>
    </div2>

  </div1>
  <div1 id="source">
    <head>Source Files</head>
    <p>All data files used to construct the entity declarations, XSLT character maps, and 
    HTML tables referenced from this document are available from 
    <loc href="https://github.com/w3c/xml-entities/">https://github.com/w3c/xml-entities/</loc>.</p>

   <ulist>
     <item><p><loc
		  href="https://github.com/w3c/xml-entities/blob/gh-pages/unicode.xml">unicode.xml</loc> master file detailing all Unicode characters with names in various entity sets and applications, TeX equivalents and other data. This file has been maintained for many years, originally by Sebastian Rahtz as part of the jadetex distribution and since around 1999 as part of the MathML specification sources by David Carlisle. The current version encodes data for all characters in Unicode <phrase role="unicode"/>.
<emph>Note: unicode.xml is over 5MB in size and may not really be suitable for direct viewing in a browser. You may prefer to save the file rather than follow the above link to unicode.xml in a browser.</emph></p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/charlist.rnc">charlist.rnc</loc> relax NG schema for unicode.xml.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/unicode.xsl">unicode.xsl</loc> XSLT stylesheet that renders unicode.xml as an HTML table.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/character-set.xml">character-set.xml</loc> the source file for this document.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/xmlspec.xsl">xmlspec.xsl</loc> a copy of the  standard xmlspec stylesheet.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/run">run</loc> small script file that builds this collection.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/xhtml1.xml">xhtml1.xml</loc> record of XHTML 1.0 entity definitions.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/mml2.xml">mml2.xml</loc> record of MathML 2.0 (second edition) entity definitions.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/unicodedata.xsl">unicodedata.xsl</loc> stylesheet that generates a new copy of unicode.xml, incorporating data from the Unicode data file, used to update unicode.xml as new versions of Unicode are released.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/entities.xsl">entities.xsl</loc> stylesheet to generate the DTD declarations for the entities.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/charmap.xsl">charmap.xsl</loc> stylesheet to generate the XSLT character maps.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/characters.xsl">characters.xsl</loc> stylesheet to generate this document, including the referenced HTML tables.</p></item>
     <item><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/schemas.xml">schemas.xml</loc> file associating XML documents with appropriate Relax NG schema.</p></item>
     <item id="catalog"><p><loc href="https://github.com/w3c/xml-entities/blob/gh-pages/catalog">catalog</loc> Sample OASIS XML catalog that redirects references to the entity or stylesheet files at https://www.w3.org/2003/entities/2007/ to the local file system at
   /etc/xml/w3c-entities. It should be edited to  refer to the location of a local copy of the files. Many XML parsers may be configured to read this catalog format, but the specific options depend on the parser being used.</p></item>
   </ulist>
     
  </div1>
  <div1 id="references"><head>References</head>
  <blist>
     <bibl id="SGML">ISO/IEC 8879:1986, Information processing &#x2014;  Text and office 
     systems &#x2014;  Standard Generalized Markup Language (SGML)</bibl>
     <bibl id="ISO9573-13-1991">ISO/IEC TR :1991, Information
technology &#x2014; SGML support facilities
Techniques for using
SGML &#x2014; Part 13: Public entity sets for
mathematics and science</bibl>
    <bibl id="Unicode">The Unicode Consortium. The Unicode Standard, Version 5.2.0, defined by: 
    The Unicode Standard, Version 5.2 (Mountain View, CA: The Unicode Consortium, 2009. ISBN 978-1-936213-00-9). Unicode 6.3 update
    (<loc
    href="https://www.unicode.org/versions/Unicode6.3.0/">https://www.unicode.org/versions/Unicode6.3.0/</loc>) 
    </bibl>
    <bibl id="Unicode15">Unicode Standard Annex 15, Version 6.3.0;
<emph><loc
href="https://www.unicode.org/reports/tr15/">Unicode Normalization Forms</loc></emph>, 
The Unicode Consortium, 2013-09-20. 
(<loc
href="https://www.unicode.org/reports/tr15/">https://www.unicode.org/reports/tr15/</loc>) 
</bibl>

    <bibl id="Unicode25">Barbara Beeton, Asmus Freytag, Murray Sargent III,
    <emph><loc
	      href="https://www.unicode.org/reports/tr25/">Unicode Support for Mathematics</loc></emph>, 
    Unicode Technical Report #25 2012-04-02.
    (<loc
    href="https://www.unicode.org/reports/tr25/">https://www.unicode.org/reports/tr25/</loc>) 
    </bibl>
    <bibl id="MathML2">David Carlisle, Patrick Ion, Robert Miner, Nico Poppelier,
    <emph><loc href="https://www.w3.org/TR/MathML2/">Mathematical Markup Language (MathML) 
    Version 2.0 (Second Edition)</loc></emph>
    W3C Recommendation 21 October 2003
    (<loc href="https://www.w3.org/TR/2003/REC-MathML2-20031021/">https://www.w3.org/TR/2003/REC-MathML2-20031021/</loc>) 
    </bibl>
    <bibl id="MathML3">David Carlisle, Patrick Ion, Robert Miner,
    <emph><loc href="https://www.w3.org/TR/MathML3/">Mathematical Markup Language (MathML) Version 3.0 2nd Edition</loc></emph>
    W3C Recommendation 10 April 2014 
    (<loc href="https://www.w3.org/TR/2014/REC-MathML3-20140410/">https://www.w3.org/TR/2014/REC-MathML3-20140410/</loc>) 
    </bibl>
    <bibl id="HTML4">Dave Raggett, Arnaud Le Hors, Ian Jacobs,
 <emph><loc href="https://www.w3.org/TR/html4/"/>HTML 4.01 Specification</emph>
W3C Recommendation 24 December 1999
(<loc
href="https://www.w3.org/TR/1999/REC-html401-19991224/">https://www.w3.org/TR/1999/REC-html401-19991224</loc>)</bibl>
<bibl id="HTML5">Robin Berjon,
    Steve Faulkner,
    Travis Leithead,
    Erika Doyle Navara,
    Edward O'Connor,
    Silvia Pfeiffer,
    Ian Hickson
<emph><loc href="https://www.w3.org/TR/html5/">HTML 5,
A vocabulary and associated APIs for HTML and XHTML</loc></emph>
W3C Candidate Recommendation 6 August 2013
(<loc href="https://www.w3.org/TR/html5/">https://www.w3.org/TR/html5/</loc>)</bibl>
<bibl id="Charmod-norm"> Fran&#xe7;ois Yergeau,
    Martin J. D&#xfc;rst,
    Richard Ishida,
    Addison Phillips,
    Misha Wolf,
    Tex Texin,
<emph><loc  href="https://www.w3.org/TR/charmod-norm/">Character Model
for the World Wide Web 1.0: Normalization</loc></emph>
W3C Working Draft 1 May 2012
(<loc href="https://www.w3.org/TR/charmod-norm/">https://www.w3.org/TR/charmod-norm/</loc>)
  </bibl>
</blist>
  </div1>
</back>
</spec>