index.html 109 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN">
<html lang="en-US-x-Hixie"><head><title>HTML 5</title><style type="text/css">
   pre { margin-left: 2em; white-space: pre-wrap; }
   h2 { margin: 3em 0 1em 0; }
   h3 { margin: 2.5em 0 1em 0; }
   h4 { margin: 2.5em 0 0.75em 0; }
   h5, h6 { margin: 2.5em 0 1em; }
   h1 + h2, h1 + h2 + h2 { margin: 0.75em 0 0.75em; }
   h2 + h3, h3 + h4, h4 + h5, h5 + h6 { margin-top: 0.5em; }
   p { margin: 1em 0; }
   hr:not(.top) { display: block; background: none; border: none; padding: 0; margin: 2em 0; height: auto; }
   dl, dd { margin-top: 0; margin-bottom: 0; }
   dt { margin-top: 0.75em; margin-bottom: 0.25em; clear: left; }
   dt + dt { margin-top: 0; }
   dd dt { margin-top: 0.25em; margin-bottom: 0; }
   dd p { margin-top: 0; }
   dd dl + p { margin-top: 1em; }
   dd table + p { margin-top: 1em; }
   p + * > li, dd li { margin: 1em 0; }
   dt, dfn { font-weight: bold; font-style: normal; }
   dt dfn { font-style: italic; }
   pre, code { font-size: inherit; font-family: monospace; font-variant: normal; }
   pre strong { color: black; font: inherit; font-weight: bold; background: yellow; }
   pre em { font-weight: bolder; font-style: normal; }
   @media screen { code { color: orangered; } code :link, code :visited { color: inherit; } }
   var sub { vertical-align: bottom; font-size: smaller; position: relative; top: 0.1em; }
   table { border-collapse: collapse; border-style: hidden hidden none hidden; }
   table thead { border-bottom: solid; }
   table tbody th:first-child { border-left: solid; }
   table td, table th { border-left: solid; border-right: solid; border-bottom: solid thin; vertical-align: top; padding: 0.2em; }
   blockquote { margin: 0 0 0 2em; border: 0; padding: 0; font-style: italic; }

   .bad, .bad *:not(.XXX) { color: gray; border-color: gray; background: transparent; }
   .matrix, .matrix td { border: none; text-align: right; }
   .matrix { margin-left: 2em; }
   .dice-example { border-collapse: collapse; border-style: hidden solid solid hidden; border-width: thin; margin-left: 3em; }
   .dice-example caption { width: 30em; font-size: smaller; font-style: italic; padding: 0.75em 0; text-align: left; }
   .dice-example td, .dice-example th { border: solid thin; width: 1.35em; height: 1.05em; text-align: center; padding: 0; }
   .applies th > * { display: block; white-space: nowrap; }
   .applies thead code { display: block; }
   .applies td { text-align: center; }
   .applies .yes { background: yellow; }

   .toc dfn, h1 dfn, h2 dfn, h3 dfn, h4 dfn, h5 dfn, h6 dfn { font: inherit; }
   img.extra { float: right; }
   pre.idl { border: solid thin; background: #EEEEEE; color: black; padding: 0.5em 1em; }
   pre.idl :link, pre.idl :visited { color: inherit; background: transparent; }
   pre.css { border: solid thin; background: #FFFFEE; color: black; padding: 0.5em 1em; }
   pre.css:first-line { color: #AAAA50; }
   dl.domintro { color: green; margin: 2em 0 2em 2em; padding: 0.5em 1em; border: none; background: #EEFFEE; }
   hr + dl.domintro, div.impl + dl.domintro { margin-top: 2.5em; margin-bottom: 1.5em; }
   dl.domintro dt, dl.domintro dt * { color: black; text-decoration: none; }
   dl.domintro dd { margin: 0.5em 0 1em 2em; padding: 0; }
   dl.domintro dd p { margin: 0.5em 0; }
   dl.switch { padding-left: 2em; }
   dl.switch > dt { text-indent: -1.5em; }
   dl.switch > dt:before { content: '\21AA'; padding: 0 0.5em 0 0; display: inline-block; width: 1em; text-align: right; line-height: 0.5em; }
   .diff-old { text-decoration: line-through; color: silver; background: transparent; }
   .diff-chg, .diff-new { text-decoration: underline; color: green; background: transparent; }
   a .diff-new { border-bottom: 1px blue solid; }

   h2 { page-break-before: always; }
   h1 + h2, hr + h2.no-toc { page-break-before: auto; }

   p > span:not([title=""]):not([class="XXX"]):not([class="impl"]), li > span:not([title=""]):not([class="XXX"]):not([class="impl"]) { border-bottom: solid #9999CC; }

   div.head { margin: 0 0 1em; padding: 1em 0 0 0; }
   div.head p { margin: 0; }
   div.head h1 { margin: 0; }
   div.head .logo { float: right; margin: 0 1em; }
   div.head .logo img { border: none } /* remove border from top image */
   div.head dl { margin: 1em 0; }
   p.copyright { font-size: x-small; font-style: oblique; margin: 0; }

   body > .toc > li { margin-top: 1em; margin-bottom: 1em; }
   body > .toc.brief > li { margin-top: 0.35em; margin-bottom: 0.35em; }
   body > .toc > li > * { margin-bottom: 0.5em; }
   body > .toc > li > * > li > * { margin-bottom: 0.25em; }
   .toc, .toc li { list-style: none; }

   .brief { margin-top: 1em; margin-bottom: 1em; line-height: 1.1; }
   .brief li { margin: 0; padding: 0; }
   .brief li p { margin: 0; padding: 0; }

   .XXX { color: #E50000; background: white; border: solid red; padding: 0.5em; margin: 1em 0; }
   .XXX > :first-child { margin-top: 0; }
   p .XXX { line-height: 3em; }
   .note { color: green; background: transparent; font-family: sans-serif; }
   .warning { color: red; background: transparent; }
   .note, .warning { font-weight: bolder; font-style: italic; }
   p.note, div.note { padding: 0.5em 2em; }
   span.note { padding: 0 2em; }
   .note p:first-child, .warning p:first-child { margin-top: 0; }
   .note p:last-child, .warning p:last-child { margin-bottom: 0; }
   .warning:before { font-style: normal; }
   p.note:before { content: 'Note: '; }
   p.warning:before { content: '\26A0 Warning! '; }

   .bookkeeping:before { display: block; content: 'Bookkeeping details'; font-weight: bolder; font-style: italic; }
   .bookkeeping { font-size: 0.8em; margin: 2em 0; }
   .bookkeeping p { margin: 0.5em 2em; display: list-item; list-style: square; }

   h4 { position: relative; z-index: 3; }
   h4 + .element, h4 + div + .element { margin-top: -2.5em; padding-top: 2em; }
   .element {
     background: #EEEEFF;
     color: black;
     margin: 0 0 1em 0.15em;
     padding: 0 1em 0.25em 0.75em;
     border-left: solid #9999FF 0.25em;
     position: relative;
     z-index: 1;
   }
   .element:before {
     position: absolute;
     z-index: 2;
     top: 0;
     left: -1.15em;
     height: 2em;
     width: 0.9em;
     background: #EEEEFF;
     content: ' ';
     border-style: none none solid solid;
     border-color: #9999FF;
     border-width: 0.25em;
   }

   .example {
     display: block;
     color: #222222;
     background: #FCFCFC;
     border-left: double;
     margin-left: 2em;
     padding-left: 1em;
   }

   .tall-and-narrow {
     font-size: 0.6em;
     column-width: 25em;
     column-gap: 1em;
     -moz-column-width: 25em;
     -moz-column-gap: 1em;
     -webkit-column-width: 25em;
     -webkit-column-gap: 1em;
   }
  </style><link href="data:text/css," rel="stylesheet" title="Complete specification"><link href="data:text/css,.impl%20%7B%20display:%20none;%20%7D" rel="alternate stylesheet" title="Author documentation only"><link href="data:text/css,.impl%20%7B%20background:%20%23FFEEEE;%20%7D" rel="alternate stylesheet" title="Highlight implementation requirements"><link href="http://www.w3.org/StyleSheets/TR/%57%33%43-WD" rel="stylesheet" type="text/css"><!-- ZZZ ED vs WD --></head><body><div class="head">
   <p><a href="http://www.w3.org/"><img alt="W3C" height="48" src="http://www.w3.org/Icons/w3c_home" width="72"></a></p>
   <h1>HTML 5</h1>
   <h2 class="no-num no-toc" id="a-vocabulary-and-associated-apis-for-html-and-xhtml">A vocabulary and associated APIs for HTML and XHTML</h2>
   <!--ZZZ:-->
   <h2 class="no-num no-toc" id="w3c-working-draft-23-april-year">W3C Working Draft 23 April 2009</h2>
   <!--<h2 class="no-num no-toc">Editor's Draft 21 April 2009</h2>-->
   <!--:ZZZ-->
   <dl><!-- ZZZ: update the month/day (twice), (un)comment out--><dt>This Version:</dt>
    <dd><a href="http://www.w3.org/TR/2009/WD-html5-20090423/">http://www.w3.org/TR/2009/WD-html5-20090423/</a></dd>
<!-- :ZZZ -->
    <dt>Latest Published Version:</dt>
    <dd><a href="http://www.w3.org/TR/html5/">http://www.w3.org/TR/html5/</a></dd>
    <dt>Latest Editor's Draft:</dt>
    <dd><a href="http://www.w3.org/html/wg/html5/">http://www.w3.org/html/wg/html5/</a></dd>
<!-- ZZZ: add the new version after it has shipped -->
    <dt>Previous Versions:</dt>
<!--ZZZ    <dd><a href="http://www.w3.org/TR/2009/WD-html5-20090423/">http://www.w3.org/TR/2009/WD-html5-20090423/</a></dd>-->
    <dd><a href="http://www.w3.org/TR/2009/WD-html5-20090212/">http://www.w3.org/TR/2009/WD-html5-20090212/</a></dd>
    <dd><a href="http://www.w3.org/TR/2008/WD-html5-20080610/">http://www.w3.org/TR/2008/WD-html5-20080610/</a></dd>
    <dd><a href="http://www.w3.org/TR/2008/WD-html5-20080122/">http://www.w3.org/TR/2008/WD-html5-20080122/</a></dd>
<!-- :ZZZ -->
    <dt>Editors:</dt>
    <dd><a href="mailto:ian@hixie.ch">Ian Hickson</a>, Google, Inc.</dd>
    <dd>David Hyatt, Apple, Inc.</dd>
   </dl><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a>
   &#169; 2009 <a href="http://www.w3.org/"><abbr title="World Wide
   Web Consortium">W3C</abbr></a><sup>&#174;</sup> (<a href="http://www.csail.mit.edu/"><abbr title="Massachusetts
   Institute of Technology">MIT</abbr></a>, <a href="http://www.ercim.org/"><abbr title="European Research
   Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C
   <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>,
   <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a>
   and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document
   use</a> rules apply.</p>
  </div><hr class="top"><h2 class="no-num no-toc" id="abstract">Abstract</h2><p>This specification defines the 5th major revision of the core
  language of the World Wide Web: the Hypertext Markup Language
  (HTML). In this version, new features are introduced to help Web
  application authors, new elements are introduced based on research
  into prevailing authoring practices, and special attention has been
  given to defining clear conformance criteria for user agents in an
  effort to improve interoperability.</p><h2 class="no-num no-toc" id="status-of-this-document">Status of this document</h2><!-- intro boilerplate (required) --><p><em>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 most recently
  formally published revision of this technical report can be found in
  the <a href="http://www.w3.org/TR/">W3C technical reports index</a>
  at http://www.w3.org/TR/.</em></p><!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- XXX this section will be moved back to just below the copyright
  notice in the header by October 2009 unless the spec as a whole has
  been transitioned to a more permissive license by that time. --><!-- XXX when moving this text, add: class="alt copyright" --><p>The <a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/">WHATWG
  version</a> of this specification is available under a license that
  permits reuse of the specification text.</p><!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- where to send feedback (required) --><p>If you wish to make comments regarding this document, please send
  them to <a href="mailto:public-html-comments@w3.org">public-html-comments@w3.org</a>
  (<a href="mailto:public-html-comments-request@w3.org?subject=subscribe">subscribe</a>,
  <a href="http://lists.w3.org/Archives/Public/public-html-comments/">archives</a>)

  <!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING SENTENCE TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST -->  
  or <a href="mailto:whatwg@whatwg.org">whatwg@whatwg.org</a> (<a href="http://lists.whatwg.org/listinfo.cgi/whatwg-whatwg.org">subscribe</a>,
  <a href="http://lists.whatwg.org/pipermail/whatwg-whatwg.org/">archives</a>),
  <!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING SENTENCE TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST -->

  or submit them using <a href="http://www.w3.org/Bugs/Public/enter_bug.cgi?product=HTML%20WG">our
  public bug database</a>.

  All feedback is welcome.</p><!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><p>We maintain <a href="http://www.whatwg.org/issues/">a list of all
  e-mails that have not yet been considered</a> and <a href="http://www.w3.org/Bugs/Public/buglist.cgi?component=Spec%20bugs&amp;component=Spec%20proposals&amp;product=HTML%20WG&amp;resolution=NEEDSINFO&amp;resolution=LATER&amp;resolution=REMIND&amp;resolution=---&amp;order=bugs.resolution%2Cbugs.priority%2C%20bugs.bug_severity">a
  list of all bug reports that have not yet been resolved</a>.</p><!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- stability (required) --><p>Implementors should be aware that this specification is not
  stable. <strong>Implementors who are not taking part in the
  discussions are likely to find the specification changing out from
  under them in incompatible ways.</strong> Vendors interested in
  implementing this specification before it eventually reaches the
  Candidate Recommendation stage should join the aforementioned
  mailing lists and take part in the discussions.</p><!-- not everyone agrees with html5 (requested before fpwd) --><p>The publication of this document by the W3C as a W3C Working
  Draft does not imply that all of the participants in the W3C HTML
  working group endorse the contents of the specification. Indeed, for
  any section of the specification, one can usually find many members
  of the working group or of the W3C as a whole who object strongly to
  the current text, the existence of the section at all, or the idea
  that the working group should even spend time discussing the concept
  of that section.</p><!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- version history or list of changes (required) --><p>The latest stable version of the editor's draft of this
  specification is always available on <a href="http://dev.w3.org/html5/spec/Overview.html">the
  W3C CVS server</a> and in the <a href="http://svn.whatwg.org/webapps/">WHATWG Subversion
  repository</a>. The <a href="http://www.whatwg.org/specs/web-apps/current-work/">latest
  editor's working copy</a> (which may contain unfinished text in
  the process of being prepared) is also available.</p><!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING LIST TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><p>There are various ways to follow the change history for the
  specification:</p><dl><dt>E-mail notifications of changes</dt>
   <dd>HTML-Diffs mailing list (diff-marked HTML versions for each change): <a href="http://lists.w3.org/Archives/Public/public-html-diffs/latest">http://lists.w3.org/Archives/Public/public-html-diffs/latest</a></dd>
   <dd>Commit-Watchers mailing list (complete source diffs): <a href="http://lists.whatwg.org/listinfo.cgi/commit-watchers-whatwg.org">http://lists.whatwg.org/listinfo.cgi/commit-watchers-whatwg.org</a></dd>
   <dt>Real-time notifications of changes:</dt>
   <dd>Generated diff-marked HTML versions for each change: <a href="http://twitter.com/HTML5">http://twitter.com/HTML5</a></dd>
   <dd>All (non-editorial) changes to the spec source: <a href="http://twitter.com/WHATWG">http://twitter.com/WHATWG</a></dd>
   <dt>Browsable version-control record of all changes:</dt>
   <dd>CVSWeb interface with side-by-side diffs: <a href="http://dev.w3.org/cvsweb/html5/spec/Overview.html">http://dev.w3.org/cvsweb/html5/spec/Overview.html</a></dd>
   <dd>Annotated summary with unified diffs: <a href="http://html5.org/tools/web-apps-tracker">http://html5.org/tools/web-apps-tracker</a></dd>
   <dd>Raw Subversion interface: <code>svn checkout http://svn.whatwg.org/webapps/</code></dd>
  </dl><!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING LIST TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- status of document, group responsible (required) --><p>The W3C <a href="http://www.w3.org/html/wg/">HTML Working
  Group</a> is the W3C working group responsible for this
  specification's progress along the W3C Recommendation
  track.
  <!--ZZZ:-->
  This specification is the 23 April 2009 Working Draft.
  <!-- This specification is the 21 April 2009 Editor's Draft. -->
  <!--:ZZZ-->
  </p><!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- relationship to other work (required) --><p>This specification is also being produced by the <a href="http://www.whatwg.org/">WHATWG</a>. The two specifications are
  identical from the table of contents onwards.</p><!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- UNDER NO CIRCUMSTANCES IS THE PRECEDING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- context and rationale (required) --><p>This specification is intended to replace (be a new version of)
  what was previously the HTML4, XHTML 1.0, and DOM2 HTML
  specifications.</p><!-- UNDER NO CIRCUMSTANCES IS THE FOLLOWING PARAGRAPH TO BE REMOVED OR EDITED WITHOUT TALKING TO IAN FIRST --><!-- required patent boilerplate --><p>This document was produced by a group operating under the <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5
  February 2004 W3C Patent Policy</a>. W3C maintains a <a href="http://www.w3.org/2004/01/pp-impl/40318/status" rel="disclosure">public list of
  any patent disclosures</a> 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 <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential
  Claim(s)</a> must disclose the information in accordance with <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section
  6 of the W3C Patent Policy</a>.</p><!--START html5--><h3 class="no-num no-toc" id="stability-0">Stability</h3><p>Different parts of this specification are at different levels of
  maturity.</p><div id="stability"></div><p class="XXX">Some of the more major known issues are marked
  like this. There are many other issues that have been raised as
  well; the issues given in this document are not the only known
  issues! Also, firing of events needs to be unified (right now some
  bubble, some don't, they all use different text to fire events,
  etc).</p><h2 class="no-num no-toc" id="contents">Table of contents</h2>
<!--begin-toc-->
<ol class="toc"><li><a href="introduction.html#introduction"><span class="secno">1 </span>Introduction</a>
  <ol><li><a href="introduction.html#background"><span class="secno">1.1 </span>Background</a></li>
   <li><a href="introduction.html#audience"><span class="secno">1.2 </span>Audience</a></li>
   <li><a href="introduction.html#scope"><span class="secno">1.3 </span>Scope</a></li>
   <li><a href="introduction.html#history-0"><span class="secno">1.4 </span>History</a></li>
   <li><a href="introduction.html#relationships-to-other-specifications"><span class="secno">1.5 </span>Relationships to other specifications</a>
    <ol><li><a href="introduction.html#relationship-to-html-4.01-and-dom2-html"><span class="secno">1.5.1 </span>Relationship to HTML 4.01 and DOM2 HTML</a></li>
     <li><a href="introduction.html#relationship-to-xhtml-1.x"><span class="secno">1.5.2 </span>Relationship to XHTML 1.x</a></li>
     <li><a href="introduction.html#relationship-to-xhtml2-and-xforms"><span class="secno">1.5.3 </span>Relationship to XHTML2 and XForms</a></li></ol></li>
   <li><a href="introduction.html#html-vs-xhtml"><span class="secno">1.6 </span>HTML vs XHTML</a></li>
   <li><a href="introduction.html#structure-of-this-specification"><span class="secno">1.7 </span>Structure of this specification</a>
    <ol><li><a href="introduction.html#how-to-read-this-specification"><span class="secno">1.7.1 </span>How to read this specification</a></li>
     <li><a href="introduction.html#typographic-conventions"><span class="secno">1.7.2 </span>Typographic conventions</a></li></ol></li></ol></li>
 <li><a href="infrastructure.html#infrastructure"><span class="secno">2 </span>Common infrastructure</a>
  <ol><li><a href="infrastructure.html#terminology"><span class="secno">2.1 </span>Terminology</a>
    <ol><li><a href="infrastructure.html#xml"><span class="secno">2.1.1 </span>XML</a></li>
     <li><a href="infrastructure.html#dom-trees"><span class="secno">2.1.2 </span>DOM trees</a></li>
     <li><a href="infrastructure.html#scripting-0"><span class="secno">2.1.3 </span>Scripting</a></li>
     <li><a href="infrastructure.html#plugins"><span class="secno">2.1.4 </span>Plugins</a></li>
     <li><a href="infrastructure.html#character-encodings"><span class="secno">2.1.5 </span>Character encodings</a></li></ol></li>
   <li><a href="infrastructure.html#conformance-requirements"><span class="secno">2.2 </span>Conformance requirements</a>
    <ol><li><a href="infrastructure.html#dependencies"><span class="secno">2.2.1 </span>Dependencies</a></li>
     <li><a href="infrastructure.html#features-defined-in-other-specifications"><span class="secno">2.2.2 </span>Features defined in other specifications</a></li>
     <li><a href="infrastructure.html#common-conformance-requirements-for-apis-exposed-to-javascript"><span class="secno">2.2.3 </span>Common conformance requirements for APIs exposed to
  JavaScript</a></li></ol></li>
   <li><a href="infrastructure.html#case-sensitivity-and-string-comparison"><span class="secno">2.3 </span>Case-sensitivity and string comparison</a></li>
   <li><a href="infrastructure.html#common-microsyntaxes"><span class="secno">2.4 </span>Common microsyntaxes</a>
    <ol><li><a href="infrastructure.html#common-parser-idioms"><span class="secno">2.4.1 </span>Common parser idioms</a></li>
     <li><a href="infrastructure.html#boolean-attributes"><span class="secno">2.4.2 </span>Boolean attributes</a></li>
     <li><a href="infrastructure.html#keywords-and-enumerated-attributes"><span class="secno">2.4.3 </span>Keywords and enumerated attributes</a></li>
     <li><a href="infrastructure.html#numbers"><span class="secno">2.4.4 </span>Numbers</a>
      <ol><li><a href="infrastructure.html#non-negative-integers"><span class="secno">2.4.4.1 </span>Non-negative integers</a></li>
       <li><a href="infrastructure.html#signed-integers"><span class="secno">2.4.4.2 </span>Signed integers</a></li>
       <li><a href="infrastructure.html#real-numbers"><span class="secno">2.4.4.3 </span>Real numbers</a></li>
       <li><a href="infrastructure.html#ratios"><span class="secno">2.4.4.4 </span>Ratios</a></li>
       <li><a href="infrastructure.html#percentages-and-dimensions"><span class="secno">2.4.4.5 </span>Percentages and lengths</a></li>
       <li><a href="infrastructure.html#lists-of-integers"><span class="secno">2.4.4.6 </span>Lists of integers</a></li>
       <li><a href="infrastructure.html#lists-of-dimensions"><span class="secno">2.4.4.7 </span>Lists of dimensions</a></li></ol></li>
     <li><a href="infrastructure.html#dates-and-times"><span class="secno">2.4.5 </span>Dates and times</a>
      <ol><li><a href="infrastructure.html#months"><span class="secno">2.4.5.1 </span>Months</a></li>
       <li><a href="infrastructure.html#dates"><span class="secno">2.4.5.2 </span>Dates</a></li>
       <li><a href="infrastructure.html#times"><span class="secno">2.4.5.3 </span>Times</a></li>
       <li><a href="infrastructure.html#local-dates-and-times"><span class="secno">2.4.5.4 </span>Local dates and times</a></li>
       <li><a href="infrastructure.html#global-dates-and-times"><span class="secno">2.4.5.5 </span>Global dates and times</a></li>
       <li><a href="infrastructure.html#weeks"><span class="secno">2.4.5.6 </span>Weeks</a></li>
       <li><a href="infrastructure.html#vaguer-moments-in-time"><span class="secno">2.4.5.7 </span>Vaguer moments in time</a></li></ol></li>
     <li><a href="infrastructure.html#colors"><span class="secno">2.4.6 </span>Colors</a></li>
     <li><a href="infrastructure.html#space-separated-tokens"><span class="secno">2.4.7 </span>Space-separated tokens</a></li>
     <li><a href="infrastructure.html#comma-separated-tokens"><span class="secno">2.4.8 </span>Comma-separated tokens</a></li>
     <li><a href="infrastructure.html#syntax-references"><span class="secno">2.4.9 </span>References</a></li></ol></li>
   <li><a href="infrastructure.html#urls"><span class="secno">2.5 </span>URLs</a>
    <ol><li><a href="infrastructure.html#terminology-0"><span class="secno">2.5.1 </span>Terminology</a></li>
     <li><a href="infrastructure.html#parsing-urls"><span class="secno">2.5.2 </span>Parsing URLs</a></li>
     <li><a href="infrastructure.html#resolving-urls"><span class="secno">2.5.3 </span>Resolving URLs</a></li>
     <li><a href="infrastructure.html#dynamic-changes-to-base-urls"><span class="secno">2.5.4 </span>Dynamic changes to base URLs</a></li>
     <li><a href="infrastructure.html#interfaces-for-url-manipulation"><span class="secno">2.5.5 </span>Interfaces for URL manipulation</a></li></ol></li>
   <li><a href="infrastructure.html#fetching-resources"><span class="secno">2.6 </span>Fetching resources</a>
    <ol><li><a href="infrastructure.html#concept-http-equivalent"><span class="secno">2.6.1 </span>Protocol concepts</a></li>
     <li><a href="infrastructure.html#encrypted-http-and-related-security-concerns"><span class="secno">2.6.2 </span>Encrypted HTTP and related security concerns</a></li></ol></li>
   <li><a href="infrastructure.html#content-type-sniffing"><span class="secno">2.7 </span>Determining the type of a resource</a>
    <ol><li><a href="infrastructure.html#content-type"><span class="secno">2.7.1 </span>Content-Type metadata</a></li>
     <li><a href="infrastructure.html#content-type-sniffing:-web-pages"><span class="secno">2.7.2 </span>Content-Type sniffing: Web pages</a></li>
     <li><a href="infrastructure.html#content-type-sniffing:-text-or-binary"><span class="secno">2.7.3 </span>Content-Type sniffing: text or binary</a></li>
     <li><a href="infrastructure.html#content-type-sniffing:-unknown-type"><span class="secno">2.7.4 </span>Content-Type sniffing: unknown type</a></li>
     <li><a href="infrastructure.html#content-type-sniffing:-image"><span class="secno">2.7.5 </span>Content-Type sniffing: image</a></li>
     <li><a href="infrastructure.html#content-type-sniffing:-feed-or-html"><span class="secno">2.7.6 </span>Content-Type sniffing: feed or HTML</a></li></ol></li>
   <li><a href="infrastructure.html#character-encodings-0"><span class="secno">2.8 </span>Character encodings</a></li>
   <li><a href="infrastructure.html#common-dom-interfaces"><span class="secno">2.9 </span>Common DOM interfaces</a>
    <ol><li><a href="infrastructure.html#reflecting-content-attributes-in-dom-attributes"><span class="secno">2.9.1 </span>Reflecting content attributes in DOM attributes</a></li>
     <li><a href="infrastructure.html#collections"><span class="secno">2.9.2 </span>Collections</a>
      <ol><li><a href="infrastructure.html#htmlcollection"><span class="secno">2.9.2.1 </span>HTMLCollection</a></li>
       <li><a href="infrastructure.html#htmlformcontrolscollection"><span class="secno">2.9.2.2 </span>HTMLFormControlsCollection</a></li>
       <li><a href="infrastructure.html#htmloptionscollection"><span class="secno">2.9.2.3 </span>HTMLOptionsCollection</a></li></ol></li>
     <li><a href="infrastructure.html#domtokenlist"><span class="secno">2.9.3 </span>DOMTokenList</a></li>
     <li><a href="infrastructure.html#safe-passing-of-structured-data"><span class="secno">2.9.4 </span>Safe passing of structured data</a></li>
     <li><a href="infrastructure.html#domstringmap"><span class="secno">2.9.5 </span>DOMStringMap</a></li>
     <li><a href="infrastructure.html#dom-feature-strings"><span class="secno">2.9.6 </span>DOM feature strings</a></li>
     <li><a href="infrastructure.html#exceptions"><span class="secno">2.9.7 </span>Exceptions</a></li>
     <li><a href="infrastructure.html#garbage-collection"><span class="secno">2.9.8 </span>Garbage collection</a></li></ol></li></ol></li>
 <li><a href="dom.html#dom"><span class="secno">3 </span>Semantics and structure of HTML documents</a>
  <ol><li><a href="dom.html#semantics-intro"><span class="secno">3.1 </span>Introduction</a></li>
   <li><a href="dom.html#documents"><span class="secno">3.2 </span>Documents</a>
    <ol><li><a href="dom.html#documents-in-the-dom"><span class="secno">3.2.1 </span>Documents in the DOM</a></li>
     <li><a href="dom.html#security"><span class="secno">3.2.2 </span>Security</a></li>
     <li><a href="dom.html#resource-metadata-management"><span class="secno">3.2.3 </span>Resource metadata management</a></li>
     <li><a href="dom.html#dom-tree-accessors"><span class="secno">3.2.4 </span>DOM tree accessors</a></li></ol></li>
   <li><a href="dom.html#elements"><span class="secno">3.3 </span>Elements</a>
    <ol><li><a href="dom.html#semantics-0"><span class="secno">3.3.1 </span>Semantics</a></li>
     <li><a href="dom.html#elements-in-the-dom"><span class="secno">3.3.2 </span>Elements in the DOM</a></li>
     <li><a href="dom.html#global-attributes"><span class="secno">3.3.3 </span>Global attributes</a>
      <ol><li><a href="dom.html#the-id-attribute"><span class="secno">3.3.3.1 </span>The <code>id</code> attribute</a></li>
       <li><a href="dom.html#the-title-attribute"><span class="secno">3.3.3.2 </span>The <code>title</code> attribute</a></li>
       <li><a href="dom.html#the-lang-and-xml:lang-attributes"><span class="secno">3.3.3.3 </span>The <code>lang</code> and <code>xml:lang</code>
  attributes</a></li>
       <li><a href="dom.html#the-xml:base-attribute-xml-only"><span class="secno">3.3.3.4 </span>The <code>xml:base</code>
  attribute (XML only)</a></li>
       <li><a href="dom.html#the-dir-attribute"><span class="secno">3.3.3.5 </span>The <code>dir</code> attribute</a></li>
       <li><a href="dom.html#classes"><span class="secno">3.3.3.6 </span>The <code>class</code> attribute</a></li>
       <li><a href="dom.html#the-style-attribute"><span class="secno">3.3.3.7 </span>The <code>style</code> attribute</a></li>
       <li><a href="dom.html#embedding-custom-non-visible-data"><span class="secno">3.3.3.8 </span>Embedding custom non-visible data</a></li></ol></li></ol></li>
   <li><a href="dom.html#content-models"><span class="secno">3.4 </span>Content models</a>
    <ol><li><a href="dom.html#kinds-of-content"><span class="secno">3.4.1 </span>Kinds of content</a>
      <ol><li><a href="dom.html#metadata-content"><span class="secno">3.4.1.1 </span>Metadata content</a></li>
       <li><a href="dom.html#flow-content"><span class="secno">3.4.1.2 </span>Flow content</a></li>
       <li><a href="dom.html#sectioning-content"><span class="secno">3.4.1.3 </span>Sectioning content</a></li>
       <li><a href="dom.html#heading-content"><span class="secno">3.4.1.4 </span>Heading content</a></li>
       <li><a href="dom.html#phrasing-content"><span class="secno">3.4.1.5 </span>Phrasing content</a></li>
       <li><a href="dom.html#embedded-content"><span class="secno">3.4.1.6 </span>Embedded content</a></li>
       <li><a href="dom.html#interactive-content"><span class="secno">3.4.1.7 </span>Interactive content</a></li></ol></li>
     <li><a href="dom.html#transparent-content-models"><span class="secno">3.4.2 </span>Transparent content models</a></li></ol></li>
   <li><a href="dom.html#paragraphs"><span class="secno">3.5 </span>Paragraphs</a></li>
   <li><a href="dom.html#apis-in-html-documents"><span class="secno">3.6 </span>APIs in HTML documents</a></li>
   <li><a href="dom.html#dynamic-markup-insertion"><span class="secno">3.7 </span>Dynamic markup insertion</a>
    <ol><li><a href="dom.html#controlling-the-input-stream"><span class="secno">3.7.1 </span>Controlling the input stream</a></li>
     <li><a href="dom.html#document.write"><span class="secno">3.7.2 </span><code title="dom-document-write">document.write()</code></a></li>
     <li><a href="dom.html#document.writeln"><span class="secno">3.7.3 </span><code title="dom-document-writeln">document.writeln()</code></a></li>
     <li><a href="dom.html#innerhtml"><span class="secno">3.7.4 </span><code title="dom-innerHTML">innerHTML</code></a></li>
     <li><a href="dom.html#outerhtml"><span class="secno">3.7.5 </span><code title="dom-outerHTML">outerHTML</code></a></li>
     <li><a href="dom.html#insertadjacenthtml"><span class="secno">3.7.6 </span><code title="dom-insertAdjacentHTML">insertAdjacentHTML()</code></a></li></ol></li></ol></li>
 <li><a href="semantics.html#semantics"><span class="secno">4 </span>The elements of HTML</a>
  <ol><li><a href="semantics.html#the-root-element"><span class="secno">4.1 </span>The root element</a>
    <ol><li><a href="semantics.html#the-html-element"><span class="secno">4.1.1 </span>The <code>html</code> element</a></li></ol></li>
   <li><a href="semantics.html#document-metadata"><span class="secno">4.2 </span>Document metadata</a>
    <ol><li><a href="semantics.html#the-head-element"><span class="secno">4.2.1 </span>The <code>head</code> element</a></li>
     <li><a href="semantics.html#the-title-element"><span class="secno">4.2.2 </span>The <code>title</code> element</a></li>
     <li><a href="semantics.html#the-base-element"><span class="secno">4.2.3 </span>The <code>base</code> element</a></li>
     <li><a href="semantics.html#the-link-element"><span class="secno">4.2.4 </span>The <code>link</code> element</a></li>
     <li><a href="semantics.html#meta"><span class="secno">4.2.5 </span>The <code>meta</code> element</a>
      <ol><li><a href="semantics.html#standard-metadata-names"><span class="secno">4.2.5.1 </span>Standard metadata names</a></li>
       <li><a href="semantics.html#other-metadata-names"><span class="secno">4.2.5.2 </span>Other metadata names</a></li>
       <li><a href="semantics.html#pragma-directives"><span class="secno">4.2.5.3 </span>Pragma directives</a></li>
       <li><a href="semantics.html#other-pragma-directives"><span class="secno">4.2.5.4 </span>Other pragma directives</a></li>
       <li><a href="semantics.html#charset"><span class="secno">4.2.5.5 </span>Specifying the document's character encoding</a></li></ol></li>
     <li><a href="semantics.html#the-style-element"><span class="secno">4.2.6 </span>The <code>style</code> element</a></li>
     <li><a href="semantics.html#styling"><span class="secno">4.2.7 </span>Styling</a></li></ol></li>
   <li><a href="semantics.html#scripting-1"><span class="secno">4.3 </span>Scripting</a>
    <ol><li><a href="semantics.html#script"><span class="secno">4.3.1 </span>The <code>script</code> element</a>
      <ol><li><a href="semantics.html#scriptingLanguages"><span class="secno">4.3.1.1 </span>Scripting languages</a></li>
       <li><a href="semantics.html#inline-documentation-for-external-scripts"><span class="secno">4.3.1.2 </span>Inline documentation for external scripts</a></li></ol></li>
     <li><a href="semantics.html#the-noscript-element"><span class="secno">4.3.2 </span>The <code>noscript</code> element</a></li></ol></li>
   <li><a href="semantics.html#sections"><span class="secno">4.4 </span>Sections</a>
    <ol><li><a href="semantics.html#the-body-element"><span class="secno">4.4.1 </span>The <code>body</code> element</a></li>
     <li><a href="semantics.html#the-section-element"><span class="secno">4.4.2 </span>The <code>section</code> element</a></li>
     <li><a href="semantics.html#the-nav-element"><span class="secno">4.4.3 </span>The <code>nav</code> element</a></li>
     <li><a href="semantics.html#the-article-element"><span class="secno">4.4.4 </span>The <code>article</code> element</a></li>
     <li><a href="semantics.html#the-aside-element"><span class="secno">4.4.5 </span>The <code>aside</code> element</a></li>
     <li><a href="semantics.html#the-h1-h2-h3-h4-h5-and-h6-elements"><span class="secno">4.4.6 </span>The <code>h1</code>, <code>h2</code>,
  <code>h3</code>, <code>h4</code>,
  <code>h5</code>, and <code>h6</code>
  elements</a></li>
     <li><a href="semantics.html#the-header-element"><span class="secno">4.4.7 </span>The <code>header</code> element</a></li>
     <li><a href="semantics.html#the-footer-element"><span class="secno">4.4.8 </span>The <code>footer</code> element</a></li>
     <li><a href="semantics.html#the-address-element"><span class="secno">4.4.9 </span>The <code>address</code> element</a></li>
     <li><a href="semantics.html#headings-and-sections"><span class="secno">4.4.10 </span>Headings and sections</a>
      <ol><li><a href="semantics.html#outlines"><span class="secno">4.4.10.1 </span>Creating an outline</a></li>
       <li><a href="semantics.html#distinguishing-site-wide-headings-from-page-headings"><span class="secno">4.4.10.2 </span>Distinguishing site-wide headings from page headings</a></li></ol></li></ol></li>
   <li><a href="semantics.html#grouping-content"><span class="secno">4.5 </span>Grouping content</a>
    <ol><li><a href="semantics.html#the-p-element"><span class="secno">4.5.1 </span>The <code>p</code> element</a></li>
     <li><a href="semantics.html#the-hr-element"><span class="secno">4.5.2 </span>The <code>hr</code> element</a></li>
     <li><a href="semantics.html#the-br-element"><span class="secno">4.5.3 </span>The <code>br</code> element</a></li>
     <li><a href="semantics.html#the-pre-element"><span class="secno">4.5.4 </span>The <code>pre</code> element</a></li>
     <li><a href="semantics.html#the-dialog-element"><span class="secno">4.5.5 </span>The <code>dialog</code> element</a></li>
     <li><a href="semantics.html#the-blockquote-element"><span class="secno">4.5.6 </span>The <code>blockquote</code> element</a></li>
     <li><a href="semantics.html#the-ol-element"><span class="secno">4.5.7 </span>The <code>ol</code> element</a></li>
     <li><a href="semantics.html#the-ul-element"><span class="secno">4.5.8 </span>The <code>ul</code> element</a></li>
     <li><a href="semantics.html#the-li-element"><span class="secno">4.5.9 </span>The <code>li</code> element</a></li>
     <li><a href="semantics.html#the-dl-element"><span class="secno">4.5.10 </span>The <code>dl</code> element</a></li>
     <li><a href="semantics.html#the-dt-element"><span class="secno">4.5.11 </span>The <code>dt</code> element</a></li>
     <li><a href="semantics.html#the-dd-element"><span class="secno">4.5.12 </span>The <code>dd</code> element</a></li>
     <li><a href="semantics.html#common-grouping-idioms"><span class="secno">4.5.13 </span>Common grouping idioms</a>
      <ol><li><a href="semantics.html#tag-clouds"><span class="secno">4.5.13.1 </span>Tag clouds</a></li></ol></li></ol></li>
   <li><a href="text-level-semantics.html#text-level-semantics"><span class="secno">4.6 </span>Text-level semantics</a>
    <ol><li><a href="text-level-semantics.html#the-a-element"><span class="secno">4.6.1 </span>The <code>a</code> element</a></li>
     <li><a href="text-level-semantics.html#the-q-element"><span class="secno">4.6.2 </span>The <code>q</code> element</a></li>
     <li><a href="text-level-semantics.html#the-cite-element"><span class="secno">4.6.3 </span>The <code>cite</code> element</a></li>
     <li><a href="text-level-semantics.html#the-em-element"><span class="secno">4.6.4 </span>The <code>em</code> element</a></li>
     <li><a href="text-level-semantics.html#the-strong-element"><span class="secno">4.6.5 </span>The <code>strong</code> element</a></li>
     <li><a href="text-level-semantics.html#the-small-element"><span class="secno">4.6.6 </span>The <code>small</code> element</a></li>
     <li><a href="text-level-semantics.html#the-mark-element"><span class="secno">4.6.7 </span>The <code>mark</code> element</a></li>
     <li><a href="text-level-semantics.html#the-dfn-element"><span class="secno">4.6.8 </span>The <code>dfn</code> element</a></li>
     <li><a href="text-level-semantics.html#the-abbr-element"><span class="secno">4.6.9 </span>The <code>abbr</code> element</a></li>
     <li><a href="text-level-semantics.html#the-time-element"><span class="secno">4.6.10 </span>The <code>time</code> element</a></li>
     <li><a href="text-level-semantics.html#the-progress-element"><span class="secno">4.6.11 </span>The <code>progress</code> element</a></li>
     <li><a href="text-level-semantics.html#the-meter-element"><span class="secno">4.6.12 </span>The <code>meter</code> element</a></li>
     <li><a href="text-level-semantics.html#the-code-element"><span class="secno">4.6.13 </span>The <code>code</code> element</a></li>
     <li><a href="text-level-semantics.html#the-var-element"><span class="secno">4.6.14 </span>The <code>var</code> element</a></li>
     <li><a href="text-level-semantics.html#the-samp-element"><span class="secno">4.6.15 </span>The <code>samp</code> element</a></li>
     <li><a href="text-level-semantics.html#the-kbd-element"><span class="secno">4.6.16 </span>The <code>kbd</code> element</a></li>
     <li><a href="text-level-semantics.html#the-sub-and-sup-elements"><span class="secno">4.6.17 </span>The <code>sub</code> and <code>sup</code> elements</a></li>
     <li><a href="text-level-semantics.html#the-span-element"><span class="secno">4.6.18 </span>The <code>span</code> element</a></li>
     <li><a href="text-level-semantics.html#the-i-element"><span class="secno">4.6.19 </span>The <code>i</code> element</a></li>
     <li><a href="text-level-semantics.html#the-b-element"><span class="secno">4.6.20 </span>The <code>b</code> element</a></li>
     <li><a href="text-level-semantics.html#the-bdo-element"><span class="secno">4.6.21 </span>The <code>bdo</code> element</a></li>
     <li><a href="text-level-semantics.html#the-ruby-element"><span class="secno">4.6.22 </span>The <code>ruby</code> element</a></li>
     <li><a href="text-level-semantics.html#the-rt-element"><span class="secno">4.6.23 </span>The <code>rt</code> element</a></li>
     <li><a href="text-level-semantics.html#the-rp-element"><span class="secno">4.6.24 </span>The <code>rp</code> element</a></li>
     <li><a href="text-level-semantics.html#usage-summary"><span class="secno">4.6.25 </span>Usage summary</a></li>
     <li><a href="text-level-semantics.html#footnotes"><span class="secno">4.6.26 </span>Footnotes</a></li></ol></li>
   <li><a href="text-level-semantics.html#edits"><span class="secno">4.7 </span>Edits</a>
    <ol><li><a href="text-level-semantics.html#the-ins-element"><span class="secno">4.7.1 </span>The <code>ins</code> element</a></li>
     <li><a href="text-level-semantics.html#the-del-element"><span class="secno">4.7.2 </span>The <code>del</code> element</a></li>
     <li><a href="text-level-semantics.html#attributes-common-to-ins-and-del-elements"><span class="secno">4.7.3 </span>Attributes common to <code>ins</code> and <code>del</code> elements</a></li>
     <li><a href="text-level-semantics.html#edits-and-paragraphs"><span class="secno">4.7.4 </span>Edits and paragraphs</a></li>
     <li><a href="text-level-semantics.html#edits-and-lists"><span class="secno">4.7.5 </span>Edits and lists</a></li></ol></li>
   <li><a href="embedded-content-0.html#embedded-content-0"><span class="secno">4.8 </span>Embedded content</a>
    <ol><li><a href="embedded-content-0.html#the-figure-element"><span class="secno">4.8.1 </span>The <code>figure</code> element</a></li>
     <li><a href="embedded-content-0.html#the-img-element"><span class="secno">4.8.2 </span>The <code>img</code> element</a>
      <ol><li><a href="embedded-content-0.html#alt"><span class="secno">4.8.2.1 </span>Requirements for providing text to act as an alternative for images</a>
        <ol><li><a href="embedded-content-0.html#a-link-or-button-containing-nothing-but-the-image"><span class="secno">4.8.2.1.1 </span>A link or button containing nothing but the image</a></li>
         <li><a href="embedded-content-0.html#a-phrase-or-paragraph-with-an-alternative-graphical-representation:-charts-diagrams-graphs-maps-illustrations"><span class="secno">4.8.2.1.2 </span>A phrase or paragraph with an alternative graphical representation: charts, diagrams, graphs, maps, illustrations</a></li>
         <li><a href="embedded-content-0.html#a-short-phrase-or-label-with-an-alternative-graphical-representation:-icons-logos"><span class="secno">4.8.2.1.3 </span>A short phrase or label with an alternative graphical representation: icons, logos</a></li>
         <li><a href="embedded-content-0.html#text-that-has-been-rendered-to-a-graphic-for-typographical-effect"><span class="secno">4.8.2.1.4 </span>Text that has been rendered to a graphic for typographical effect</a></li>
         <li><a href="embedded-content-0.html#a-graphical-representation-of-some-of-the-surrounding-text"><span class="secno">4.8.2.1.5 </span>A graphical representation of some of the surrounding text</a></li>
         <li><a href="embedded-content-0.html#a-purely-decorative-image-that-doesn-t-add-any-information"><span class="secno">4.8.2.1.6 </span>A purely decorative image that doesn't add any information</a></li>
         <li><a href="embedded-content-0.html#a-group-of-images-that-form-a-single-larger-picture-with-no-links"><span class="secno">4.8.2.1.7 </span>A group of images that form a single larger picture with no links</a></li>
         <li><a href="embedded-content-0.html#a-group-of-images-that-form-a-single-larger-picture-with-links"><span class="secno">4.8.2.1.8 </span>A group of images that form a single larger picture with links</a></li>
         <li><a href="embedded-content-0.html#a-key-part-of-the-content"><span class="secno">4.8.2.1.9 </span>A key part of the content</a></li>
         <li><a href="embedded-content-0.html#an-image-not-intended-for-the-user"><span class="secno">4.8.2.1.10 </span>An image not intended for the user</a></li>
         <li><a href="embedded-content-0.html#an-image-in-an-e-mail-or-document-intended-for-a-specific-person-who-is-known-to-be-able-to-view-images"><span class="secno">4.8.2.1.11 </span>An image in an e-mail or document intended for a specific person who is known to be able to view images</a></li>
         <li><a href="embedded-content-0.html#general-guidelines"><span class="secno">4.8.2.1.12 </span>General guidelines</a></li>
         <li><a href="embedded-content-0.html#guidance-for-markup-generators"><span class="secno">4.8.2.1.13 </span>Guidance for markup generators</a></li>
         <li><a href="embedded-content-0.html#guidance-for-conformance-checkers"><span class="secno">4.8.2.1.14 </span>Guidance for conformance checkers</a></li></ol></li></ol></li>
     <li><a href="embedded-content-0.html#the-iframe-element"><span class="secno">4.8.3 </span>The <code>iframe</code> element</a></li>
     <li><a href="embedded-content-0.html#the-embed-element"><span class="secno">4.8.4 </span>The <code>embed</code> element</a></li>
     <li><a href="embedded-content-0.html#the-object-element"><span class="secno">4.8.5 </span>The <code>object</code> element</a></li>
     <li><a href="embedded-content-0.html#the-param-element"><span class="secno">4.8.6 </span>The <code>param</code> element</a></li>
     <li><a href="video.html#video"><span class="secno">4.8.7 </span>The <code>video</code> element</a>
      <ol><li><a href="video.html#video-and-audio-codecs-for-video-elements"><span class="secno">4.8.7.1 </span>Video and audio codecs for <code>video</code> elements</a></li></ol></li>
     <li><a href="video.html#audio"><span class="secno">4.8.8 </span>The <code>audio</code> element</a>
      <ol><li><a href="video.html#audio-codecs-for-audio-elements"><span class="secno">4.8.8.1 </span>Audio codecs for <code>audio</code> elements</a></li></ol></li>
     <li><a href="video.html#the-source-element"><span class="secno">4.8.9 </span>The <code>source</code> element</a></li>
     <li><a href="video.html#media-elements"><span class="secno">4.8.10 </span>Media elements</a>
      <ol><li><a href="video.html#error-codes"><span class="secno">4.8.10.1 </span>Error codes</a></li>
       <li><a href="video.html#location-of-the-media-resource"><span class="secno">4.8.10.2 </span>Location of the media resource</a></li>
       <li><a href="video.html#media-types"><span class="secno">4.8.10.3 </span>Media types</a></li>
       <li><a href="video.html#network-states"><span class="secno">4.8.10.4 </span>Network states</a></li>
       <li><a href="video.html#loading-the-media-resource"><span class="secno">4.8.10.5 </span>Loading the media resource</a></li>
       <li><a href="video.html#offsets-into-the-media-resource"><span class="secno">4.8.10.6 </span>Offsets into the media resource</a></li>
       <li><a href="video.html#the-ready-states"><span class="secno">4.8.10.7 </span>The ready states</a></li>
       <li><a href="video.html#cue-ranges"><span class="secno">4.8.10.8 </span>Cue ranges</a></li>
       <li><a href="video.html#playing-the-media-resource"><span class="secno">4.8.10.9 </span>Playing the media resource</a></li>
       <li><a href="video.html#seeking"><span class="secno">4.8.10.10 </span>Seeking</a></li>
       <li><a href="video.html#user-interface"><span class="secno">4.8.10.11 </span>User interface</a></li>
       <li><a href="video.html#time-ranges"><span class="secno">4.8.10.12 </span>Time ranges</a></li>
       <li><a href="video.html#mediaevents"><span class="secno">4.8.10.13 </span>Event summary</a></li>
       <li><a href="video.html#security-and-privacy-considerations"><span class="secno">4.8.10.14 </span>Security and privacy considerations</a></li></ol></li>
     <li><a href="the-canvas-element.html#the-canvas-element"><span class="secno">4.8.11 </span>The <code>canvas</code> element</a>
      <ol><li><a href="the-canvas-element.html#the-2d-context"><span class="secno">4.8.11.1 </span>The 2D context</a>
        <ol><li><a href="the-canvas-element.html#the-canvas-state"><span class="secno">4.8.11.1.1 </span>The canvas state</a></li>
         <li><a href="the-canvas-element.html#transformations"><span class="secno">4.8.11.1.2 </span>Transformations</a></li>
         <li><a href="the-canvas-element.html#compositing"><span class="secno">4.8.11.1.3 </span>Compositing</a></li>
         <li><a href="the-canvas-element.html#colors-and-styles"><span class="secno">4.8.11.1.4 </span>Colors and styles</a></li>
         <li><a href="the-canvas-element.html#line-styles"><span class="secno">4.8.11.1.5 </span>Line styles</a></li>
         <li><a href="the-canvas-element.html#shadows"><span class="secno">4.8.11.1.6 </span>Shadows</a></li>
         <li><a href="the-canvas-element.html#simple-shapes-rectangles"><span class="secno">4.8.11.1.7 </span>Simple shapes (rectangles)</a></li>
         <li><a href="the-canvas-element.html#complex-shapes-paths"><span class="secno">4.8.11.1.8 </span>Complex shapes (paths)</a></li>
         <li><a href="the-canvas-element.html#text"><span class="secno">4.8.11.1.9 </span>Text</a></li>
         <li><a href="the-canvas-element.html#images"><span class="secno">4.8.11.1.10 </span>Images</a></li>
         <li><a href="the-canvas-element.html#pixel-manipulation"><span class="secno">4.8.11.1.11 </span>Pixel manipulation</a></li>
         <li><a href="the-canvas-element.html#drawing-model"><span class="secno">4.8.11.1.12 </span>Drawing model</a></li></ol></li>
       <li><a href="the-canvas-element.html#color-spaces-and-color-correction"><span class="secno">4.8.11.2 </span>Color spaces and color correction</a></li>
       <li><a href="the-canvas-element.html#security-with-canvas-elements"><span class="secno">4.8.11.3 </span>Security with <code>canvas</code> elements</a></li></ol></li>
     <li><a href="the-canvas-element.html#the-map-element"><span class="secno">4.8.12 </span>The <code>map</code> element</a></li>
     <li><a href="the-canvas-element.html#the-area-element"><span class="secno">4.8.13 </span>The <code>area</code> element</a></li>
     <li><a href="the-canvas-element.html#image-maps"><span class="secno">4.8.14 </span>Image maps</a>
      <ol><li><a href="the-canvas-element.html#authoring"><span class="secno">4.8.14.1 </span>Authoring</a></li>
       <li><a href="the-canvas-element.html#processing-model"><span class="secno">4.8.14.2 </span>Processing model</a></li></ol></li>
     <li><a href="the-canvas-element.html#mathml"><span class="secno">4.8.15 </span>MathML</a></li>
     <li><a href="the-canvas-element.html#svg"><span class="secno">4.8.16 </span>SVG</a></li>
     <li><a href="the-canvas-element.html#dimension-attributes"><span class="secno">4.8.17 </span>Dimension attributes</a></li></ol></li>
   <li><a href="tabular-data.html#tabular-data"><span class="secno">4.9 </span>Tabular data</a>
    <ol><li><a href="tabular-data.html#table-intro"><span class="secno">4.9.1 </span>Introduction</a></li>
     <li><a href="tabular-data.html#the-table-element"><span class="secno">4.9.2 </span>The <code>table</code> element</a></li>
     <li><a href="tabular-data.html#the-caption-element"><span class="secno">4.9.3 </span>The <code>caption</code> element</a></li>
     <li><a href="tabular-data.html#the-colgroup-element"><span class="secno">4.9.4 </span>The <code>colgroup</code> element</a></li>
     <li><a href="tabular-data.html#the-col-element"><span class="secno">4.9.5 </span>The <code>col</code> element</a></li>
     <li><a href="tabular-data.html#the-tbody-element"><span class="secno">4.9.6 </span>The <code>tbody</code> element</a></li>
     <li><a href="tabular-data.html#the-thead-element"><span class="secno">4.9.7 </span>The <code>thead</code> element</a></li>
     <li><a href="tabular-data.html#the-tfoot-element"><span class="secno">4.9.8 </span>The <code>tfoot</code> element</a></li>
     <li><a href="tabular-data.html#the-tr-element"><span class="secno">4.9.9 </span>The <code>tr</code> element</a></li>
     <li><a href="tabular-data.html#the-td-element"><span class="secno">4.9.10 </span>The <code>td</code> element</a></li>
     <li><a href="tabular-data.html#the-th-element"><span class="secno">4.9.11 </span>The <code>th</code> element</a></li>
     <li><a href="tabular-data.html#attributes-common-to-td-and-th-elements"><span class="secno">4.9.12 </span>Attributes common to <code>td</code> and <code>th</code> elements</a></li>
     <li><a href="tabular-data.html#processing-model-0"><span class="secno">4.9.13 </span>Processing model</a>
      <ol><li><a href="tabular-data.html#forming-a-table"><span class="secno">4.9.13.1 </span>Forming a table</a></li>
       <li><a href="tabular-data.html#header-and-data-cell-semantics"><span class="secno">4.9.13.2 </span>Forming relationships between data cells and header cells</a></li></ol></li></ol></li>
   <li><a href="forms.html#forms"><span class="secno">4.10 </span>Forms</a>
    <ol><li><a href="forms.html#the-form-element"><span class="secno">4.10.1 </span>The <code>form</code> element</a></li>
     <li><a href="forms.html#the-fieldset-element"><span class="secno">4.10.2 </span>The <code>fieldset</code> element</a></li>
     <li><a href="forms.html#the-label-element"><span class="secno">4.10.3 </span>The <code>label</code> element</a></li>
     <li><a href="forms.html#the-input-element"><span class="secno">4.10.4 </span>The <code>input</code> element</a>
      <ol><li><a href="forms.html#states-of-the-type-attribute"><span class="secno">4.10.4.1 </span>States of the <code title="attr-input-type">type</code> attribute</a>
        <ol><li><a href="forms.html#hidden-state"><span class="secno">4.10.4.1.1 </span>Hidden state</a></li>
         <li><a href="forms.html#text-state-and-search-state"><span class="secno">4.10.4.1.2 </span>Text state and Search state</a></li>
         <li><a href="forms.html#url-state"><span class="secno">4.10.4.1.3 </span>URL state</a></li>
         <li><a href="forms.html#e-mail-state"><span class="secno">4.10.4.1.4 </span>E-mail state</a></li>
         <li><a href="forms.html#password-state"><span class="secno">4.10.4.1.5 </span>Password state</a></li>
         <li><a href="forms.html#date-and-time-state"><span class="secno">4.10.4.1.6 </span>Date and Time state</a></li>
         <li><a href="forms.html#date-state"><span class="secno">4.10.4.1.7 </span>Date state</a></li>
         <li><a href="forms.html#month-state"><span class="secno">4.10.4.1.8 </span>Month state</a></li>
         <li><a href="forms.html#week-state"><span class="secno">4.10.4.1.9 </span>Week state</a></li>
         <li><a href="forms.html#time-state"><span class="secno">4.10.4.1.10 </span>Time state</a></li>
         <li><a href="forms.html#local-date-and-time-state"><span class="secno">4.10.4.1.11 </span>Local Date and Time state</a></li>
         <li><a href="forms.html#number-state"><span class="secno">4.10.4.1.12 </span>Number state</a></li>
         <li><a href="forms.html#range-state"><span class="secno">4.10.4.1.13 </span>Range state</a></li>
         <li><a href="forms.html#color-state"><span class="secno">4.10.4.1.14 </span>Color state</a></li>
         <li><a href="forms.html#checkbox-state"><span class="secno">4.10.4.1.15 </span>Checkbox state</a></li>
         <li><a href="forms.html#radio-button-state"><span class="secno">4.10.4.1.16 </span>Radio Button state</a></li>
         <li><a href="forms.html#file-upload-state"><span class="secno">4.10.4.1.17 </span>File Upload state</a></li>
         <li><a href="forms.html#submit-button-state"><span class="secno">4.10.4.1.18 </span>Submit Button state</a></li>
         <li><a href="forms.html#image-button-state"><span class="secno">4.10.4.1.19 </span>Image Button state</a></li>
         <li><a href="forms.html#reset-button-state"><span class="secno">4.10.4.1.20 </span>Reset Button state</a></li>
         <li><a href="forms.html#button-state"><span class="secno">4.10.4.1.21 </span>Button state</a></li></ol></li>
       <li><a href="forms.html#common-input-element-attributes"><span class="secno">4.10.4.2 </span>Common <code>input</code> element attributes</a>
        <ol><li><a href="forms.html#the-autocomplete-attribute"><span class="secno">4.10.4.2.1 </span>The <code title="attr-input-autocomplete">autocomplete</code> attribute</a></li>
         <li><a href="forms.html#the-list-attribute"><span class="secno">4.10.4.2.2 </span>The <code title="attr-input-list">list</code> attribute</a></li>
         <li><a href="forms.html#the-readonly-attribute"><span class="secno">4.10.4.2.3 </span>The <code title="attr-input-readonly">readonly</code> attribute</a></li>
         <li><a href="forms.html#the-size-attribute"><span class="secno">4.10.4.2.4 </span>The <code title="attr-input-size">size</code> attribute</a></li>
         <li><a href="forms.html#the-required-attribute"><span class="secno">4.10.4.2.5 </span>The <code title="attr-input-required">required</code> attribute</a></li>
         <li><a href="forms.html#the-multiple-attribute"><span class="secno">4.10.4.2.6 </span>The <code title="attr-input-multiple">multiple</code> attribute</a></li>
         <li><a href="forms.html#the-maxlength-attribute"><span class="secno">4.10.4.2.7 </span>The <code title="attr-input-maxlength">maxlength</code> attribute</a></li>
         <li><a href="forms.html#the-pattern-attribute"><span class="secno">4.10.4.2.8 </span>The <code title="attr-input-pattern">pattern</code> attribute</a></li>
         <li><a href="forms.html#the-min-and-max-attributes"><span class="secno">4.10.4.2.9 </span>The <code title="attr-input-min">min</code> and <code title="attr-input-max">max</code> attributes</a></li>
         <li><a href="forms.html#the-step-attribute"><span class="secno">4.10.4.2.10 </span>The <code title="attr-input-step">step</code> attribute</a></li>
         <li><a href="forms.html#the-placeholder-attribute"><span class="secno">4.10.4.2.11 </span>The <code title="attr-input-placeholder">placeholder</code> attribute</a></li></ol></li>
       <li><a href="forms.html#common-input-element-apis"><span class="secno">4.10.4.3 </span>Common <code>input</code> element APIs</a></li>
       <li><a href="forms.html#common-event-behaviors"><span class="secno">4.10.4.4 </span>Common event behaviors</a></li></ol></li>
     <li><a href="forms.html#the-button-element"><span class="secno">4.10.5 </span>The <code>button</code> element</a></li>
     <li><a href="forms.html#the-select-element"><span class="secno">4.10.6 </span>The <code>select</code> element</a></li>
     <li><a href="forms.html#the-datalist-element"><span class="secno">4.10.7 </span>The <code>datalist</code> element</a></li>
     <li><a href="forms.html#the-optgroup-element"><span class="secno">4.10.8 </span>The <code>optgroup</code> element</a></li>
     <li><a href="forms.html#the-option-element"><span class="secno">4.10.9 </span>The <code>option</code> element</a></li>
     <li><a href="forms.html#the-textarea-element"><span class="secno">4.10.10 </span>The <code>textarea</code> element</a></li>
     <li><a href="forms.html#the-keygen-element"><span class="secno">4.10.11 </span>The <code>keygen</code> element</a></li>
     <li><a href="forms.html#the-output-element"><span class="secno">4.10.12 </span>The <code>output</code> element</a></li>
     <li><a href="forms.html#association-of-controls-and-forms"><span class="secno">4.10.13 </span>Association of controls and forms</a></li>
     <li><a href="forms.html#attributes-common-to-form-controls"><span class="secno">4.10.14 </span>Attributes common to form controls</a>
      <ol><li><a href="forms.html#naming-form-controls"><span class="secno">4.10.14.1 </span>Naming form controls</a></li>
       <li><a href="forms.html#enabling-and-disabling-form-controls"><span class="secno">4.10.14.2 </span>Enabling and disabling form controls</a></li>
       <li><a href="forms.html#a-form-control-s-value"><span class="secno">4.10.14.3 </span>A form control's value</a></li>
       <li><a href="forms.html#autofocusing-a-form-control"><span class="secno">4.10.14.4 </span>Autofocusing a form control</a></li>
       <li><a href="forms.html#limiting-user-input-length"><span class="secno">4.10.14.5 </span>Limiting user input length</a></li>
       <li><a href="forms.html#form-submission"><span class="secno">4.10.14.6 </span>Form submission</a></li></ol></li>
     <li><a href="forms.html#constraints"><span class="secno">4.10.15 </span>Constraints</a>
      <ol><li><a href="forms.html#definitions"><span class="secno">4.10.15.1 </span>Definitions</a></li>
       <li><a href="forms.html#constraint-validation"><span class="secno">4.10.15.2 </span>Constraint validation</a></li>
       <li><a href="forms.html#the-constraint-validation-api"><span class="secno">4.10.15.3 </span>The constraint validation API</a></li>
       <li><a href="forms.html#security-0"><span class="secno">4.10.15.4 </span>Security</a></li></ol></li>
     <li><a href="forms.html#form-submission-0"><span class="secno">4.10.16 </span>Form submission</a>
      <ol><li><a href="forms.html#introduction-0"><span class="secno">4.10.16.1 </span>Introduction</a></li>
       <li><a href="forms.html#implicit-submission"><span class="secno">4.10.16.2 </span>Implicit submission</a></li>
       <li><a href="forms.html#form-submission-algorithm"><span class="secno">4.10.16.3 </span>Form submission algorithm</a></li>
       <li><a href="forms.html#url-encoded-form-data"><span class="secno">4.10.16.4 </span>URL-encoded form data</a></li>
       <li><a href="forms.html#multipart-form-data"><span class="secno">4.10.16.5 </span>Multipart form data</a></li>
       <li><a href="forms.html#plain-text-form-data"><span class="secno">4.10.16.6 </span>Plain text form data</a></li></ol></li>
     <li><a href="forms.html#resetting-a-form"><span class="secno">4.10.17 </span>Resetting a form</a></li>
     <li><a href="forms.html#event-dispatch"><span class="secno">4.10.18 </span>Event dispatch</a></li></ol></li>
   <li><a href="interactive-elements.html#interactive-elements"><span class="secno">4.11 </span>Interactive elements</a>
    <ol><li><a href="interactive-elements.html#the-details-element"><span class="secno">4.11.1 </span>The <code>details</code> element</a></li>
     <li><a href="interactive-elements.html#datagrid"><span class="secno">4.11.2 </span>The <code>datagrid</code> element</a>
      <ol><li><a href="interactive-elements.html#introduction-1"><span class="secno">4.11.2.1 </span>Introduction</a>
        <ol><li><a href="interactive-elements.html#example:-a-datagrid-backed-by-a-static-table-element"><span class="secno">4.11.2.1.1 </span>Example: a <code>datagrid</code> backed by a static <code>table</code> element</a></li>
         <li><a href="interactive-elements.html#example:-a-datagrid-backed-by-nested-ol-elements"><span class="secno">4.11.2.1.2 </span>Example: a <code>datagrid</code> backed by nested <code>ol</code> elements</a></li>
         <li><a href="interactive-elements.html#example:-a-datagrid-backed-by-a-server"><span class="secno">4.11.2.1.3 </span>Example: a <code>datagrid</code> backed by a server</a></li></ol></li>
       <li><a href="interactive-elements.html#populating-the-datagrid"><span class="secno">4.11.2.2 </span>Populating the <code>datagrid</code></a>
        <ol><li><a href="interactive-elements.html#the-listener"><span class="secno">4.11.2.2.1 </span>The listener</a></li>
         <li><a href="interactive-elements.html#the-columns"><span class="secno">4.11.2.2.2 </span>The columns</a></li>
         <li><a href="interactive-elements.html#the-rows"><span class="secno">4.11.2.2.3 </span>The rows</a></li>
         <li><a href="interactive-elements.html#the-cells"><span class="secno">4.11.2.2.4 </span>The cells</a></li></ol></li>
       <li><a href="interactive-elements.html#listening-to-notifications-from-the-datagrid"><span class="secno">4.11.2.3 </span>Listening to notifications from the <code>datagrid</code></a></li></ol></li>
     <li><a href="interactive-elements.html#the-command"><span class="secno">4.11.3 </span>The <code>command</code> element</a></li>
     <li><a href="interactive-elements.html#the-bb-element"><span class="secno">4.11.4 </span>The <code>bb</code> element</a>
      <ol><li><a href="interactive-elements.html#browser-button-types"><span class="secno">4.11.4.1 </span>Browser button types</a>
        <ol><li><a href="interactive-elements.html#the-make-application-state"><span class="secno">4.11.4.1.1 </span>The <i>make application</i> state</a></li></ol></li></ol></li>
     <li><a href="interactive-elements.html#menus"><span class="secno">4.11.5 </span>The <code>menu</code> element</a>
      <ol><li><a href="interactive-elements.html#menus-intro"><span class="secno">4.11.5.1 </span>Introduction</a></li>
       <li><a href="interactive-elements.html#building-menus-and-tool-bars"><span class="secno">4.11.5.2 </span>Building menus and tool bars</a></li>
       <li><a href="interactive-elements.html#context-menus"><span class="secno">4.11.5.3 </span>Context menus</a></li>
       <li><a href="interactive-elements.html#tool-bars"><span class="secno">4.11.5.4 </span>Tool bars</a></li></ol></li>
     <li><a href="interactive-elements.html#commands"><span class="secno">4.11.6 </span>Commands</a>
      <ol><li><a href="interactive-elements.html#using-the-a-element-to-define-a-command"><span class="secno">4.11.6.1 </span>Using the <code>a</code> element to define a command</a></li>
       <li><a href="interactive-elements.html#using-the-button-element-to-define-a-command"><span class="secno">4.11.6.2 </span>Using the <code>button</code> element to define a command</a></li>
       <li><a href="interactive-elements.html#using-the-input-element-to-define-a-command"><span class="secno">4.11.6.3 </span>Using the <code>input</code> element to define a command</a></li>
       <li><a href="interactive-elements.html#using-the-option-element-to-define-a-command"><span class="secno">4.11.6.4 </span>Using the <code>option</code> element to define a command</a></li>
       <li><a href="interactive-elements.html#using-the-command-element-to-define-a-command"><span class="secno">4.11.6.5 </span>Using the <code>command</code> element to define
  a command</a></li>
       <li><a href="interactive-elements.html#using-the-bb-element-to-define-a-command"><span class="secno">4.11.6.6 </span>Using the <code>bb</code> element to define a command</a></li></ol></li></ol></li>
   <li><a href="interactive-elements.html#miscellaneous-elements"><span class="secno">4.12 </span>Miscellaneous elements</a>
    <ol><li><a href="interactive-elements.html#the-legend-element"><span class="secno">4.12.1 </span>The <code>legend</code> element</a></li>
     <li><a href="interactive-elements.html#the-div-element"><span class="secno">4.12.2 </span>The <code>div</code> element</a></li></ol></li>
   <li><a href="interactive-elements.html#matching-html-elements-using-selectors"><span class="secno">4.13 </span>Matching HTML elements using selectors</a></li></ol></li>
 <li><a href="browsers.html#browsers"><span class="secno">5 </span>Web browsers</a>
  <ol><li><a href="browsers.html#windows"><span class="secno">5.1 </span>Browsing contexts</a>
    <ol><li><a href="browsers.html#nested-browsing-contexts"><span class="secno">5.1.1 </span>Nested browsing contexts</a>
      <ol><li><a href="browsers.html#navigating-nested-browsing-contexts-in-the-dom"><span class="secno">5.1.1.1 </span>Navigating nested browsing contexts in the DOM</a></li></ol></li>
     <li><a href="browsers.html#auxiliary-browsing-contexts"><span class="secno">5.1.2 </span>Auxiliary browsing contexts</a>
      <ol><li><a href="browsers.html#navigating-auxiliary-browsing-contexts-in-the-dom"><span class="secno">5.1.2.1 </span>Navigating auxiliary browsing contexts in the DOM</a></li></ol></li>
     <li><a href="browsers.html#secondary-browsing-contexts"><span class="secno">5.1.3 </span>Secondary browsing contexts</a></li>
     <li><a href="browsers.html#security-1"><span class="secno">5.1.4 </span>Security</a></li>
     <li><a href="browsers.html#groupings-of-browsing-contexts"><span class="secno">5.1.5 </span>Groupings of browsing contexts</a></li>
     <li><a href="browsers.html#browsing-context-names"><span class="secno">5.1.6 </span>Browsing context names</a></li></ol></li>
   <li><a href="browsers.html#the-windowproxy-object"><span class="secno">5.2 </span>The <code>WindowProxy</code> object</a></li>
   <li><a href="browsers.html#the-window-object"><span class="secno">5.3 </span>The <code>Window</code> object</a>
    <ol><li><a href="browsers.html#security-2"><span class="secno">5.3.1 </span>Security</a></li>
     <li><a href="browsers.html#apis-for-creating-and-navigating-browsing-contexts-by-name"><span class="secno">5.3.2 </span>APIs for creating and navigating browsing contexts by name</a></li>
     <li><a href="browsers.html#accessing-other-browsing-contexts"><span class="secno">5.3.3 </span>Accessing other browsing contexts</a></li>
     <li><a href="browsers.html#named-access-on-the-window-object"><span class="secno">5.3.4 </span>Named access on the <code>Window</code> object</a></li>
     <li><a href="browsers.html#garbage-collection-and-browsing-contexts"><span class="secno">5.3.5 </span>Garbage collection and browsing contexts</a></li>
     <li><a href="browsers.html#browser-interface-elements"><span class="secno">5.3.6 </span>Browser interface elements</a></li></ol></li>
   <li><a href="browsers.html#origin"><span class="secno">5.4 </span>Origin</a>
    <ol><li><a href="browsers.html#relaxing-the-same-origin-restriction"><span class="secno">5.4.1 </span>Relaxing the same-origin restriction</a></li></ol></li>
   <li><a href="browsers.html#scripting"><span class="secno">5.5 </span>Scripting</a>
    <ol><li><a href="browsers.html#introduction-2"><span class="secno">5.5.1 </span>Introduction</a></li>
     <li><a href="browsers.html#enabling-and-disabling-scripting"><span class="secno">5.5.2 </span>Enabling and disabling scripting</a></li>
     <li><a href="browsers.html#processing-model-1"><span class="secno">5.5.3 </span>Processing model</a>
      <ol><li><a href="browsers.html#definitions-0"><span class="secno">5.5.3.1 </span>Definitions</a></li>
       <li><a href="browsers.html#calling-scripts"><span class="secno">5.5.3.2 </span>Calling scripts</a></li>
       <li><a href="browsers.html#creating-scripts"><span class="secno">5.5.3.3 </span>Creating scripts</a></li>
       <li><a href="browsers.html#killing-scripts"><span class="secno">5.5.3.4 </span>Killing scripts</a></li></ol></li>
     <li><a href="browsers.html#event-loops"><span class="secno">5.5.4 </span>Event loops</a>
      <ol><li><a href="browsers.html#definitions-1"><span class="secno">5.5.4.1 </span>Definitions</a></li>
       <li><a href="browsers.html#processing-model-2"><span class="secno">5.5.4.2 </span>Processing model</a></li>
       <li><a href="browsers.html#generic-task-sources"><span class="secno">5.5.4.3 </span>Generic task sources</a></li></ol></li>
     <li><a href="browsers.html#javascript-protocol"><span class="secno">5.5.5 </span>The <code title="">javascript:</code> protocol</a></li>
     <li><a href="browsers.html#events"><span class="secno">5.5.6 </span>Events</a>
      <ol><li><a href="browsers.html#event-handler-attributes"><span class="secno">5.5.6.1 </span>Event handler attributes</a></li>
       <li><a href="browsers.html#event-handler-attributes-on-elements-document-objects-and-window-objects"><span class="secno">5.5.6.2 </span>Event handler attributes on elements, <code>Document</code> objects, and <code>Window</code> objects</a></li>
       <li><a href="browsers.html#event-firing"><span class="secno">5.5.6.3 </span>Event firing</a></li>
       <li><a href="browsers.html#events-and-the-window-object"><span class="secno">5.5.6.4 </span>Events and the <code>Window</code> object</a></li>
       <li><a href="browsers.html#runtime-script-errors"><span class="secno">5.5.6.5 </span>Runtime script errors</a></li></ol></li></ol></li>
   <li><a href="browsers.html#user-prompts"><span class="secno">5.6 </span>User prompts</a>
    <ol><li><a href="browsers.html#simple-dialogs"><span class="secno">5.6.1 </span>Simple dialogs</a></li>
     <li><a href="browsers.html#printing"><span class="secno">5.6.2 </span>Printing</a></li>
     <li><a href="browsers.html#dialogs-implemented-using-separate-documents"><span class="secno">5.6.3 </span>Dialogs implemented using separate documents</a></li></ol></li>
   <li><a href="browsers.html#system-state-and-capabilities"><span class="secno">5.7 </span>System state and capabilities</a>
    <ol><li><a href="browsers.html#client-identification"><span class="secno">5.7.1 </span>Client identification</a></li>
     <li><a href="browsers.html#custom-handlers"><span class="secno">5.7.2 </span>Custom protocol and content handlers</a>
      <ol><li><a href="browsers.html#security-and-privacy"><span class="secno">5.7.2.1 </span>Security and privacy</a></li>
       <li><a href="browsers.html#sample-handler-impl"><span class="secno">5.7.2.2 </span>Sample user interface</a></li></ol></li>
     <li><a href="browsers.html#manually-releasing-the-storage-mutex"><span class="secno">5.7.3 </span>Manually releasing the storage mutex</a></li></ol></li>
   <li><a href="offline.html#offline"><span class="secno">5.8 </span>Offline Web applications</a>
    <ol><li><a href="offline.html#introduction-3"><span class="secno">5.8.1 </span>Introduction</a></li>
     <li><a href="offline.html#appcache"><span class="secno">5.8.2 </span>Application caches</a></li>
     <li><a href="offline.html#manifests"><span class="secno">5.8.3 </span>The cache manifest syntax</a>
      <ol><li><a href="offline.html#a-sample-manifest"><span class="secno">5.8.3.1 </span>A sample manifest</a></li>
       <li><a href="offline.html#writing-cache-manifests"><span class="secno">5.8.3.2 </span>Writing cache manifests</a></li>
       <li><a href="offline.html#parsing-cache-manifests"><span class="secno">5.8.3.3 </span>Parsing cache manifests</a></li></ol></li>
     <li><a href="offline.html#updating-an-application-cache"><span class="secno">5.8.4 </span>Updating an application cache</a></li>
     <li><a href="offline.html#matching-a-fallback-namespace"><span class="secno">5.8.5 </span>Matching a fallback namespace</a></li>
     <li><a href="offline.html#the-application-cache-selection-algorithm"><span class="secno">5.8.6 </span>The application cache selection algorithm</a></li>
     <li><a href="offline.html#changesToNetworkingModel"><span class="secno">5.8.7 </span>Changes to the networking model</a></li>
     <li><a href="offline.html#application-cache-api"><span class="secno">5.8.8 </span>Application cache API</a></li>
     <li><a href="offline.html#browser-state"><span class="secno">5.8.9 </span>Browser state</a></li></ol></li>
   <li><a href="history.html#history"><span class="secno">5.9 </span>Session history and navigation</a>
    <ol><li><a href="history.html#the-session-history-of-browsing-contexts"><span class="secno">5.9.1 </span>The session history of browsing contexts</a></li>
     <li><a href="history.html#the-history-interface"><span class="secno">5.9.2 </span>The <code>History</code> interface</a></li>
     <li><a href="history.html#activating-state-object-entries"><span class="secno">5.9.3 </span>Activating state object entries</a></li>
     <li><a href="history.html#the-location-interface"><span class="secno">5.9.4 </span>The <code>Location</code> interface</a>
      <ol><li><a href="history.html#security-3"><span class="secno">5.9.4.1 </span>Security</a></li></ol></li>
     <li><a href="history.html#history-notes"><span class="secno">5.9.5 </span>Implementation notes for session history</a></li></ol></li>
   <li><a href="history.html#browsing-the-web"><span class="secno">5.10 </span>Browsing the Web</a>
    <ol><li><a href="history.html#navigating-across-documents"><span class="secno">5.10.1 </span>Navigating across documents</a></li>
     <li><a href="history.html#read-html"><span class="secno">5.10.2 </span>Page load processing model for HTML files</a></li>
     <li><a href="history.html#read-xml"><span class="secno">5.10.3 </span>Page load processing model for XML files</a></li>
     <li><a href="history.html#read-text"><span class="secno">5.10.4 </span>Page load processing model for text files</a></li>
     <li><a href="history.html#read-image"><span class="secno">5.10.5 </span>Page load processing model for images</a></li>
     <li><a href="history.html#read-plugin"><span class="secno">5.10.6 </span>Page load processing model for content that uses plugins</a></li>
     <li><a href="history.html#read-ua-inline"><span class="secno">5.10.7 </span>Page load processing model for inline content that doesn't have a DOM</a></li>
     <li><a href="history.html#scroll-to-fragid"><span class="secno">5.10.8 </span>Navigating to a fragment identifier</a></li>
     <li><a href="history.html#history-traversal"><span class="secno">5.10.9 </span>History traversal</a></li>
     <li><a href="history.html#unloading-documents"><span class="secno">5.10.10 </span>Unloading documents</a>
      <ol><li><a href="history.html#event-definition"><span class="secno">5.10.10.1 </span>Event definition</a></li></ol></li></ol></li>
   <li><a href="history.html#links"><span class="secno">5.11 </span>Links</a>
    <ol><li><a href="history.html#hyperlink-elements"><span class="secno">5.11.1 </span>Hyperlink elements</a></li>
     <li><a href="history.html#following-hyperlinks"><span class="secno">5.11.2 </span>Following hyperlinks</a>
      <ol><li><a href="history.html#hyperlink-auditing"><span class="secno">5.11.2.1 </span>Hyperlink auditing</a></li></ol></li>
     <li><a href="history.html#linkTypes"><span class="secno">5.11.3 </span>Link types</a>
      <ol><li><a href="history.html#link-type-alternate"><span class="secno">5.11.3.1 </span>Link type "<code>alternate</code>"</a></li>
       <li><a href="history.html#link-type-archives"><span class="secno">5.11.3.2 </span>Link type "<code>archives</code>"</a></li>
       <li><a href="history.html#link-type-author"><span class="secno">5.11.3.3 </span>Link type "<code>author</code>"</a></li>
       <li><a href="history.html#link-type-bookmark"><span class="secno">5.11.3.4 </span>Link type "<code>bookmark</code>"</a></li>
       <li><a href="history.html#link-type-external"><span class="secno">5.11.3.5 </span>Link type "<code>external</code>"</a></li>
       <li><a href="history.html#link-type-feed"><span class="secno">5.11.3.6 </span>Link type "<code>feed</code>"</a></li>
       <li><a href="history.html#link-type-help"><span class="secno">5.11.3.7 </span>Link type "<code>help</code>"</a></li>
       <li><a href="history.html#rel-icon"><span class="secno">5.11.3.8 </span>Link type "<code>icon</code>"</a></li>
       <li><a href="history.html#link-type-license"><span class="secno">5.11.3.9 </span>Link type "<code>license</code>"</a></li>
       <li><a href="history.html#link-type-nofollow"><span class="secno">5.11.3.10 </span>Link type "<code>nofollow</code>"</a></li>
       <li><a href="history.html#link-type-noreferrer"><span class="secno">5.11.3.11 </span>Link type "<code>noreferrer</code>"</a></li>
       <li><a href="history.html#link-type-pingback"><span class="secno">5.11.3.12 </span>Link type "<code>pingback</code>"</a></li>
       <li><a href="history.html#link-type-prefetch"><span class="secno">5.11.3.13 </span>Link type "<code>prefetch</code>"</a></li>
       <li><a href="history.html#link-type-search"><span class="secno">5.11.3.14 </span>Link type "<code>search</code>"</a></li>
       <li><a href="history.html#link-type-stylesheet"><span class="secno">5.11.3.15 </span>Link type "<code>stylesheet</code>"</a></li>
       <li><a href="history.html#link-type-sidebar"><span class="secno">5.11.3.16 </span>Link type "<code>sidebar</code>"</a></li>
       <li><a href="history.html#link-type-tag"><span class="secno">5.11.3.17 </span>Link type "<code>tag</code>"</a></li>
       <li><a href="history.html#hierarchical-link-types"><span class="secno">5.11.3.18 </span>Hierarchical link types</a>
        <ol><li><a href="history.html#link-type-index"><span class="secno">5.11.3.18.1 </span>Link type "<code>index</code>"</a></li>
         <li><a href="history.html#link-type-up"><span class="secno">5.11.3.18.2 </span>Link type "<code>up</code>"</a></li></ol></li>
       <li><a href="history.html#sequential-link-types"><span class="secno">5.11.3.19 </span>Sequential link types</a>
        <ol><li><a href="history.html#link-type-first"><span class="secno">5.11.3.19.1 </span>Link type "<code>first</code>"</a></li>
         <li><a href="history.html#link-type-last"><span class="secno">5.11.3.19.2 </span>Link type "<code>last</code>"</a></li>
         <li><a href="history.html#link-type-next"><span class="secno">5.11.3.19.3 </span>Link type "<code>next</code>"</a></li>
         <li><a href="history.html#link-type-prev"><span class="secno">5.11.3.19.4 </span>Link type "<code>prev</code>"</a></li></ol></li>
       <li><a href="history.html#other-link-types"><span class="secno">5.11.3.20 </span>Other link types</a></li></ol></li></ol></li></ol></li>
 <li><a href="editing.html#editing"><span class="secno">6 </span>User Interaction</a>
  <ol><li><a href="editing.html#editing-intro"><span class="secno">6.1 </span>Introduction</a></li>
   <li><a href="editing.html#the-hidden-attribute"><span class="secno">6.2 </span>The <code>hidden</code> attribute</a></li>
   <li><a href="editing.html#activation"><span class="secno">6.3 </span>Activation</a></li>
   <li><a href="editing.html#scrolling-elements-into-view"><span class="secno">6.4 </span>Scrolling elements into view</a></li>
   <li><a href="editing.html#focus"><span class="secno">6.5 </span>Focus</a>
    <ol><li><a href="editing.html#sequential-focus-navigation"><span class="secno">6.5.1 </span>Sequential focus navigation</a></li>
     <li><a href="editing.html#focus-management"><span class="secno">6.5.2 </span>Focus management</a></li>
     <li><a href="editing.html#document-level-focus-apis"><span class="secno">6.5.3 </span>Document-level focus APIs</a></li>
     <li><a href="editing.html#element-level-focus-apis"><span class="secno">6.5.4 </span>Element-level focus APIs</a></li></ol></li>
   <li><a href="editing.html#selection"><span class="secno">6.6 </span>The text selection APIs</a>
    <ol><li><a href="editing.html#documentSelection"><span class="secno">6.6.1 </span>APIs for the browsing context selection</a></li>
     <li><a href="editing.html#textFieldSelection"><span class="secno">6.6.2 </span>APIs for the text field selections</a></li></ol></li>
   <li><a href="editing.html#contenteditable"><span class="secno">6.7 </span>The <code title="attr-contenteditable">contenteditable</code> attribute</a>
    <ol><li><a href="editing.html#user-editing-actions"><span class="secno">6.7.1 </span>User editing actions</a></li>
     <li><a href="editing.html#making-entire-documents-editable"><span class="secno">6.7.2 </span>Making entire documents editable</a></li></ol></li>
   <li><a href="editing.html#spelling-and-grammar-checking"><span class="secno">6.8 </span>Spelling and grammar checking</a></li>
   <li><a href="editing.html#dnd"><span class="secno">6.9 </span>Drag and drop</a>
    <ol><li><a href="editing.html#introduction-4"><span class="secno">6.9.1 </span>Introduction</a></li>
     <li><a href="editing.html#the-dragevent-and-datatransfer-interfaces"><span class="secno">6.9.2 </span>The <code>DragEvent</code> and <code>DataTransfer</code> interfaces</a></li>
     <li><a href="editing.html#events-fired-during-a-drag-and-drop-action"><span class="secno">6.9.3 </span>Events fired during a drag-and-drop action</a></li>
     <li><a href="editing.html#drag-and-drop-processing-model"><span class="secno">6.9.4 </span>Drag-and-drop processing model</a>
      <ol><li><a href="editing.html#when-the-drag-and-drop-operation-starts-or-ends-in-another-document"><span class="secno">6.9.4.1 </span>When the drag-and-drop operation starts or ends in another
  document</a></li>
       <li><a href="editing.html#when-the-drag-and-drop-operation-starts-or-ends-in-another-application"><span class="secno">6.9.4.2 </span>When the drag-and-drop operation starts or ends in another
  application</a></li></ol></li>
     <li><a href="editing.html#the-draggable-attribute"><span class="secno">6.9.5 </span>The <code>draggable</code> attribute</a></li>
     <li><a href="editing.html#copy-and-paste"><span class="secno">6.9.6 </span>Copy and paste</a>
      <ol><li><a href="editing.html#copy-to-clipboard"><span class="secno">6.9.6.1 </span>Copy to clipboard</a></li>
       <li><a href="editing.html#cut-to-clipboard"><span class="secno">6.9.6.2 </span>Cut to clipboard</a></li>
       <li><a href="editing.html#paste-from-clipboard"><span class="secno">6.9.6.3 </span>Paste from clipboard</a></li>
       <li><a href="editing.html#paste-from-selection"><span class="secno">6.9.6.4 </span>Paste from selection</a></li></ol></li>
     <li><a href="editing.html#security-risks-in-the-drag-and-drop-model"><span class="secno">6.9.7 </span>Security risks in the drag-and-drop model</a></li></ol></li>
   <li><a href="editing.html#undo"><span class="secno">6.10 </span>Undo history</a>
    <ol><li><a href="editing.html#introduction-5"><span class="secno">6.10.1 </span>Introduction</a></li>
     <li><a href="editing.html#definitions-2"><span class="secno">6.10.2 </span>Definitions</a></li>
     <li><a href="editing.html#the-undomanager-interface"><span class="secno">6.10.3 </span>The <code>UndoManager</code> interface</a></li>
     <li><a href="editing.html#undo:-moving-back-in-the-undo-transaction-history"><span class="secno">6.10.4 </span>Undo: moving back in the undo transaction history</a></li>
     <li><a href="editing.html#redo:-moving-forward-in-the-undo-transaction-history"><span class="secno">6.10.5 </span>Redo: moving forward in the undo transaction history</a></li>
     <li><a href="editing.html#the-undomanagerevent-interface-and-the-undo-and-redo-events"><span class="secno">6.10.6 </span>The <code>UndoManagerEvent</code> interface and the <code title="event-undo">undo</code> and <code title="event-redo">redo</code> events</a></li>
     <li><a href="editing.html#implementation-notes"><span class="secno">6.10.7 </span>Implementation notes</a></li></ol></li>
   <li><a href="editing.html#command-apis"><span class="secno">6.11 </span>Command APIs</a></li></ol></li>
 <li><a href="comms.html#comms"><span class="secno">7 </span>Communication</a>
  <ol><li><a href="comms.html#event-definitions"><span class="secno">7.1 </span>Event definitions</a></li>
   <li><a href="comms.html#crossDocumentMessages"><span class="secno">7.2 </span>Cross-document messaging</a>
    <ol><li><a href="comms.html#introduction-6"><span class="secno">7.2.1 </span>Introduction</a></li>
     <li><a href="comms.html#security-4"><span class="secno">7.2.2 </span>Security</a>
      <ol><li><a href="comms.html#authors"><span class="secno">7.2.2.1 </span>Authors</a></li>
       <li><a href="comms.html#user-agents"><span class="secno">7.2.2.2 </span>User agents</a></li></ol></li>
     <li><a href="comms.html#posting-messages"><span class="secno">7.2.3 </span>Posting messages</a></li>
     <li><a href="comms.html#posting-messages-with-message-ports"><span class="secno">7.2.4 </span>Posting messages with message ports</a></li></ol></li>
   <li><a href="comms.html#channel-messaging"><span class="secno">7.3 </span>Channel messaging</a>
    <ol><li><a href="comms.html#introduction-7"><span class="secno">7.3.1 </span>Introduction</a></li>
     <li><a href="comms.html#message-channels"><span class="secno">7.3.2 </span>Message channels</a></li>
     <li><a href="comms.html#message-ports"><span class="secno">7.3.3 </span>Message ports</a>
      <ol><li><a href="comms.html#ports-and-garbage-collection"><span class="secno">7.3.3.1 </span>Ports and garbage collection</a></li></ol></li></ol></li></ol></li>
 <li><a href="syntax.html#syntax"><span class="secno">8 </span>The HTML syntax</a>
  <ol><li><a href="syntax.html#writing-html-documents"><span class="secno">8.1 </span>Writing HTML documents</a>
    <ol><li><a href="syntax.html#the-doctype"><span class="secno">8.1.1 </span>The DOCTYPE</a></li>
     <li><a href="syntax.html#elements-0"><span class="secno">8.1.2 </span>Elements</a>
      <ol><li><a href="syntax.html#start-tags"><span class="secno">8.1.2.1 </span>Start tags</a></li>
       <li><a href="syntax.html#end-tags"><span class="secno">8.1.2.2 </span>End tags</a></li>
       <li><a href="syntax.html#attributes"><span class="secno">8.1.2.3 </span>Attributes</a></li>
       <li><a href="syntax.html#optional-tags"><span class="secno">8.1.2.4 </span>Optional tags</a></li>
       <li><a href="syntax.html#element-restrictions"><span class="secno">8.1.2.5 </span>Restrictions on content models</a></li>
       <li><a href="syntax.html#cdata-rcdata-restrictions"><span class="secno">8.1.2.6 </span>Restrictions on the contents of CDATA and RCDATA elements</a></li></ol></li>
     <li><a href="syntax.html#text-0"><span class="secno">8.1.3 </span>Text</a>
      <ol><li><a href="syntax.html#newlines"><span class="secno">8.1.3.1 </span>Newlines</a></li></ol></li>
     <li><a href="syntax.html#character-references"><span class="secno">8.1.4 </span>Character references</a></li>
     <li><a href="syntax.html#cdata-sections"><span class="secno">8.1.5 </span>CDATA sections</a></li>
     <li><a href="syntax.html#comments"><span class="secno">8.1.6 </span>Comments</a></li></ol></li>
   <li><a href="syntax.html#parsing"><span class="secno">8.2 </span>Parsing HTML documents</a>
    <ol><li><a href="syntax.html#overview-of-the-parsing-model"><span class="secno">8.2.1 </span>Overview of the parsing model</a></li>
     <li><a href="syntax.html#the-input-stream"><span class="secno">8.2.2 </span>The input stream</a>
      <ol><li><a href="syntax.html#determining-the-character-encoding"><span class="secno">8.2.2.1 </span>Determining the character encoding</a></li>
       <li><a href="syntax.html#preprocessing-the-input-stream"><span class="secno">8.2.2.2 </span>Preprocessing the input stream</a></li>
       <li><a href="syntax.html#changing-the-encoding-while-parsing"><span class="secno">8.2.2.3 </span>Changing the encoding while parsing</a></li></ol></li>
     <li><a href="syntax.html#parse-state"><span class="secno">8.2.3 </span>Parse state</a>
      <ol><li><a href="syntax.html#the-insertion-mode"><span class="secno">8.2.3.1 </span>The insertion mode</a></li>
       <li><a href="syntax.html#the-stack-of-open-elements"><span class="secno">8.2.3.2 </span>The stack of open elements</a></li>
       <li><a href="syntax.html#the-list-of-active-formatting-elements"><span class="secno">8.2.3.3 </span>The list of active formatting elements</a></li>
       <li><a href="syntax.html#the-element-pointers"><span class="secno">8.2.3.4 </span>The element pointers</a></li>
       <li><a href="syntax.html#other-parsing-state-flags"><span class="secno">8.2.3.5 </span>Other parsing state flags</a></li></ol></li>
     <li><a href="syntax.html#tokenization"><span class="secno">8.2.4 </span>Tokenization</a>
      <ol><li><a href="syntax.html#data-state"><span class="secno">8.2.4.1 </span>Data state</a></li>
       <li><a href="syntax.html#character-reference-data-state"><span class="secno">8.2.4.2 </span>Character reference data state</a></li>
       <li><a href="syntax.html#tag-open-state"><span class="secno">8.2.4.3 </span>Tag open state</a></li>
       <li><a href="syntax.html#close-tag-open-state"><span class="secno">8.2.4.4 </span>Close tag open state</a></li>
       <li><a href="syntax.html#tag-name-state"><span class="secno">8.2.4.5 </span>Tag name state</a></li>
       <li><a href="syntax.html#before-attribute-name-state"><span class="secno">8.2.4.6 </span>Before attribute name state</a></li>
       <li><a href="syntax.html#attribute-name-state"><span class="secno">8.2.4.7 </span>Attribute name state</a></li>
       <li><a href="syntax.html#after-attribute-name-state"><span class="secno">8.2.4.8 </span>After attribute name state</a></li>
       <li><a href="syntax.html#before-attribute-value-state"><span class="secno">8.2.4.9 </span>Before attribute value state</a></li>
       <li><a href="syntax.html#attribute-value-double-quoted-state"><span class="secno">8.2.4.10 </span>Attribute value (double-quoted) state</a></li>
       <li><a href="syntax.html#attribute-value-single-quoted-state"><span class="secno">8.2.4.11 </span>Attribute value (single-quoted) state</a></li>
       <li><a href="syntax.html#attribute-value-unquoted-state"><span class="secno">8.2.4.12 </span>Attribute value (unquoted) state</a></li>
       <li><a href="syntax.html#character-reference-in-attribute-value-state"><span class="secno">8.2.4.13 </span>Character reference in attribute value state</a></li>
       <li><a href="syntax.html#after-attribute-value-quoted-state"><span class="secno">8.2.4.14 </span>After attribute value (quoted) state</a></li>
       <li><a href="syntax.html#self-closing-start-tag-state"><span class="secno">8.2.4.15 </span>Self-closing start tag state</a></li>
       <li><a href="syntax.html#bogus-comment-state"><span class="secno">8.2.4.16 </span>Bogus comment state</a></li>
       <li><a href="syntax.html#markup-declaration-open-state"><span class="secno">8.2.4.17 </span>Markup declaration open state</a></li>
       <li><a href="syntax.html#comment-start-state"><span class="secno">8.2.4.18 </span>Comment start state</a></li>
       <li><a href="syntax.html#comment-start-dash-state"><span class="secno">8.2.4.19 </span>Comment start dash state</a></li>
       <li><a href="syntax.html#comment-state"><span class="secno">8.2.4.20 </span>Comment state</a></li>
       <li><a href="syntax.html#comment-end-dash-state"><span class="secno">8.2.4.21 </span>Comment end dash state</a></li>
       <li><a href="syntax.html#comment-end-state"><span class="secno">8.2.4.22 </span>Comment end state</a></li>
       <li><a href="syntax.html#doctype-state"><span class="secno">8.2.4.23 </span>DOCTYPE state</a></li>
       <li><a href="syntax.html#before-doctype-name-state"><span class="secno">8.2.4.24 </span>Before DOCTYPE name state</a></li>
       <li><a href="syntax.html#doctype-name-state"><span class="secno">8.2.4.25 </span>DOCTYPE name state</a></li>
       <li><a href="syntax.html#after-doctype-name-state"><span class="secno">8.2.4.26 </span>After DOCTYPE name state</a></li>
       <li><a href="syntax.html#before-doctype-public-identifier-state"><span class="secno">8.2.4.27 </span>Before DOCTYPE public identifier state</a></li>
       <li><a href="syntax.html#doctype-public-identifier-double-quoted-state"><span class="secno">8.2.4.28 </span>DOCTYPE public identifier (double-quoted) state</a></li>
       <li><a href="syntax.html#doctype-public-identifier-single-quoted-state"><span class="secno">8.2.4.29 </span>DOCTYPE public identifier (single-quoted) state</a></li>
       <li><a href="syntax.html#after-doctype-public-identifier-state"><span class="secno">8.2.4.30 </span>After DOCTYPE public identifier state</a></li>
       <li><a href="syntax.html#before-doctype-system-identifier-state"><span class="secno">8.2.4.31 </span>Before DOCTYPE system identifier state</a></li>
       <li><a href="syntax.html#doctype-system-identifier-double-quoted-state"><span class="secno">8.2.4.32 </span>DOCTYPE system identifier (double-quoted) state</a></li>
       <li><a href="syntax.html#doctype-system-identifier-single-quoted-state"><span class="secno">8.2.4.33 </span>DOCTYPE system identifier (single-quoted) state</a></li>
       <li><a href="syntax.html#after-doctype-system-identifier-state"><span class="secno">8.2.4.34 </span>After DOCTYPE system identifier state</a></li>
       <li><a href="syntax.html#bogus-doctype-state"><span class="secno">8.2.4.35 </span>Bogus DOCTYPE state</a></li>
       <li><a href="syntax.html#cdata-section-state"><span class="secno">8.2.4.36 </span>CDATA section state</a></li>
       <li><a href="syntax.html#tokenizing-character-references"><span class="secno">8.2.4.37 </span>Tokenizing character references</a></li></ol></li>
     <li><a href="syntax.html#tree-construction"><span class="secno">8.2.5 </span>Tree construction</a>
      <ol><li><a href="syntax.html#creating-and-inserting-elements"><span class="secno">8.2.5.1 </span>Creating and inserting elements</a></li>
       <li><a href="syntax.html#closing-elements-that-have-implied-end-tags"><span class="secno">8.2.5.2 </span>Closing elements that have implied end tags</a></li>
       <li><a href="syntax.html#foster-parenting"><span class="secno">8.2.5.3 </span>Foster parenting</a></li>
       <li><a href="syntax.html#the-initial-insertion-mode"><span class="secno">8.2.5.4 </span>The "initial" insertion mode</a></li>
       <li><a href="syntax.html#the-before-html-insertion-mode"><span class="secno">8.2.5.5 </span>The "before html" insertion mode</a></li>
       <li><a href="syntax.html#the-before-head-insertion-mode"><span class="secno">8.2.5.6 </span>The "before head" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-inhead"><span class="secno">8.2.5.7 </span>The "in head" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-inheadnoscript"><span class="secno">8.2.5.8 </span>The "in head noscript" insertion mode</a></li>
       <li><a href="syntax.html#the-after-head-insertion-mode"><span class="secno">8.2.5.9 </span>The "after head" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-inbody"><span class="secno">8.2.5.10 </span>The "in body" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-incdata"><span class="secno">8.2.5.11 </span>The "in CDATA/RCDATA" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-intable"><span class="secno">8.2.5.12 </span>The "in table" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-incaption"><span class="secno">8.2.5.13 </span>The "in caption" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-incolgroup"><span class="secno">8.2.5.14 </span>The "in column group" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-intbody"><span class="secno">8.2.5.15 </span>The "in table body" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-intr"><span class="secno">8.2.5.16 </span>The "in row" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-intd"><span class="secno">8.2.5.17 </span>The "in cell" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-inselect"><span class="secno">8.2.5.18 </span>The "in select" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-inselectintable"><span class="secno">8.2.5.19 </span>The "in select in table" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-inforeign"><span class="secno">8.2.5.20 </span>The "in foreign content" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-afterbody"><span class="secno">8.2.5.21 </span>The "after body" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-inframeset"><span class="secno">8.2.5.22 </span>The "in frameset" insertion mode</a></li>
       <li><a href="syntax.html#parsing-main-afterframeset"><span class="secno">8.2.5.23 </span>The "after frameset" insertion mode</a></li>
       <li><a href="syntax.html#the-after-after-body-insertion-mode"><span class="secno">8.2.5.24 </span>The "after after body" insertion mode</a></li>
       <li><a href="syntax.html#the-after-after-frameset-insertion-mode"><span class="secno">8.2.5.25 </span>The "after after frameset" insertion mode</a></li></ol></li>
     <li><a href="syntax.html#the-end"><span class="secno">8.2.6 </span>The end</a></li>
     <li><a href="syntax.html#coercing-an-html-dom-into-an-infoset"><span class="secno">8.2.7 </span>Coercing an HTML DOM into an infoset</a></li></ol></li>
   <li><a href="syntax.html#namespaces"><span class="secno">8.3 </span>Namespaces</a></li>
   <li><a href="syntax.html#serializing-html-fragments"><span class="secno">8.4 </span>Serializing HTML fragments</a></li>
   <li><a href="syntax.html#parsing-html-fragments"><span class="secno">8.5 </span>Parsing HTML fragments</a></li>
   <li><a href="named-character-references.html#named-character-references"><span class="secno">8.6 </span>Named character references</a></li></ol></li>
 <li><a href="the-xhtml-syntax.html#the-xhtml-syntax"><span class="secno">9 </span>The XHTML syntax</a>
  <ol><li><a href="the-xhtml-syntax.html#writing-xhtml-documents"><span class="secno">9.1 </span>Writing XHTML documents</a></li>
   <li><a href="the-xhtml-syntax.html#parsing-xhtml-documents"><span class="secno">9.2 </span>Parsing XHTML documents</a></li>
   <li><a href="the-xhtml-syntax.html#serializing-xhtml-fragments"><span class="secno">9.3 </span>Serializing XHTML fragments</a></li>
   <li><a href="the-xhtml-syntax.html#parsing-xhtml-fragments"><span class="secno">9.4 </span>Parsing XHTML fragments</a></li></ol></li>
 <li><a href="the-xhtml-syntax.html#rendering"><span class="secno">10 </span>Rendering</a>
  <ol><li><a href="the-xhtml-syntax.html#introduction-8"><span class="secno">10.1 </span>Introduction</a></li>
   <li><a href="the-xhtml-syntax.html#the-css-user-agent-style-sheet-and-presentational-hints"><span class="secno">10.2 </span>The CSS user agent style sheet and presentational hints</a>
    <ol><li><a href="the-xhtml-syntax.html#introduction-9"><span class="secno">10.2.1 </span>Introduction</a></li>
     <li><a href="the-xhtml-syntax.html#display-types"><span class="secno">10.2.2 </span>Display types</a></li>
     <li><a href="the-xhtml-syntax.html#margins-and-padding"><span class="secno">10.2.3 </span>Margins and padding</a></li>
     <li><a href="the-xhtml-syntax.html#alignment"><span class="secno">10.2.4 </span>Alignment</a></li>
     <li><a href="the-xhtml-syntax.html#fonts-and-colors"><span class="secno">10.2.5 </span>Fonts and colors</a></li>
     <li><a href="the-xhtml-syntax.html#punctuation-and-decorations"><span class="secno">10.2.6 </span>Punctuation and decorations</a></li>
     <li><a href="the-xhtml-syntax.html#resetting-rules-for-inherited-properties"><span class="secno">10.2.7 </span>Resetting rules for inherited properties</a></li>
     <li><a href="the-xhtml-syntax.html#the-hr-element-0"><span class="secno">10.2.8 </span>The <code>hr</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-fieldset-element-0"><span class="secno">10.2.9 </span>The <code>fieldset</code> element</a></li></ol></li>
   <li><a href="the-xhtml-syntax.html#replaced-elements"><span class="secno">10.3 </span>Replaced elements</a>
    <ol><li><a href="the-xhtml-syntax.html#embedded-content-1"><span class="secno">10.3.1 </span>Embedded content</a></li>
     <li><a href="the-xhtml-syntax.html#images-0"><span class="secno">10.3.2 </span>Images</a></li>
     <li><a href="the-xhtml-syntax.html#attributes-for-embedded-content-and-images"><span class="secno">10.3.3 </span>Attributes for embedded content and images</a></li>
     <li><a href="the-xhtml-syntax.html#image-maps-0"><span class="secno">10.3.4 </span>Image maps</a></li>
     <li><a href="the-xhtml-syntax.html#tool-bars-0"><span class="secno">10.3.5 </span>Tool bars</a></li></ol></li>
   <li><a href="the-xhtml-syntax.html#bindings"><span class="secno">10.4 </span>Bindings</a>
    <ol><li><a href="the-xhtml-syntax.html#introduction-10"><span class="secno">10.4.1 </span>Introduction</a></li>
     <li><a href="the-xhtml-syntax.html#the-bb-element-0"><span class="secno">10.4.2 </span>The <code>bb</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-button-element-0"><span class="secno">10.4.3 </span>The <code>button</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-datagrid-element"><span class="secno">10.4.4 </span>The <code>datagrid</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-details-element-0"><span class="secno">10.4.5 </span>The <code>details</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-input-element-as-a-text-entry-widget"><span class="secno">10.4.6 </span>The <code>input</code> element as a text entry widget</a></li>
     <li><a href="the-xhtml-syntax.html#the-input-element-as-domain-specific-widgets"><span class="secno">10.4.7 </span>The <code>input</code> element as domain-specific widgets</a></li>
     <li><a href="the-xhtml-syntax.html#the-input-element-as-a-range-control"><span class="secno">10.4.8 </span>The <code>input</code> element as a range control</a></li>
     <li><a href="the-xhtml-syntax.html#the-input-element-as-a-color-well"><span class="secno">10.4.9 </span>The <code>input</code> element as a color well</a></li>
     <li><a href="the-xhtml-syntax.html#the-input-element-as-a-check-box-and-radio-button-widgets"><span class="secno">10.4.10 </span>The <code>input</code> element as a check box and radio button widgets</a></li>
     <li><a href="the-xhtml-syntax.html#the-input-element-as-a-file-upload-control"><span class="secno">10.4.11 </span>The <code>input</code> element as a file upload control</a></li>
     <li><a href="the-xhtml-syntax.html#the-input-element-as-a-button"><span class="secno">10.4.12 </span>The <code>input</code> element as a button</a></li>
     <li><a href="the-xhtml-syntax.html#the-marquee-element"><span class="secno">10.4.13 </span>The <code>marquee</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-meter-element-0"><span class="secno">10.4.14 </span>The <code>meter</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-progress-element-0"><span class="secno">10.4.15 </span>The <code>progress</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-select-element-0"><span class="secno">10.4.16 </span>The <code>select</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-textarea-element-0"><span class="secno">10.4.17 </span>The <code>textarea</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-keygen-element-0"><span class="secno">10.4.18 </span>The <code>keygen</code> element</a></li></ol></li>
   <li><a href="the-xhtml-syntax.html#frames-and-framesets"><span class="secno">10.5 </span>Frames and framesets</a></li>
   <li><a href="the-xhtml-syntax.html#interactive-media"><span class="secno">10.6 </span>Interactive media</a>
    <ol><li><a href="the-xhtml-syntax.html#links-forms-and-navigation"><span class="secno">10.6.1 </span>Links, forms, and navigation</a></li>
     <li><a href="the-xhtml-syntax.html#the-mark-element-0"><span class="secno">10.6.2 </span>The <code>mark</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-title-attribute-0"><span class="secno">10.6.3 </span>The <code title="attr-title">title</code> attribute</a></li></ol></li>
   <li><a href="the-xhtml-syntax.html#print-media"><span class="secno">10.7 </span>Print media</a></li>
   <li><a href="the-xhtml-syntax.html#interaction-with-css"><span class="secno">10.8 </span>Interaction with CSS</a></li></ol></li>
 <li><a href="the-xhtml-syntax.html#obsolete-features"><span class="secno">11 </span>Obsolete features</a>
  <ol><li><a href="the-xhtml-syntax.html#self-contained-features"><span class="secno">11.1 </span>Self-contained features</a>
    <ol><li><a href="the-xhtml-syntax.html#the-applet-element"><span class="secno">11.1.1 </span>The <code>applet</code> element</a></li>
     <li><a href="the-xhtml-syntax.html#the-marquee-element-0"><span class="secno">11.1.2 </span>The <code>marquee</code> element</a></li></ol></li>
   <li><a href="the-xhtml-syntax.html#other-elements-and-attributes"><span class="secno">11.2 </span>Other elements and attributes</a></li>
   <li><a href="the-xhtml-syntax.html#other-dom-apis"><span class="secno">11.3 </span>Other DOM APIs</a></li>
   <li><a href="the-xhtml-syntax.html#conformance-checkers-0"><span class="secno">11.4 </span>Conformance checkers</a></li></ol></li>
 <li><a href="no.html#no"><span class="secno">12 </span>Things that you can't do with this specification because
  they are better handled using other technologies that are further
  described herein</a>
  <ol><li><a href="no.html#localization"><span class="secno">12.1 </span>Localization</a></li>
   <li><a href="no.html#declarative-3d-scenes"><span class="secno">12.2 </span>Declarative 3D scenes</a></li>
   <li><a href="no.html#timers"><span class="secno">12.3 </span>Timers</a></li>
   <li><a href="no.html#rendering-and-the-dom"><span class="secno">12.4 </span>Rendering and the DOM</a></li></ol></li>
 <li><a class="no-num" href="index.html#index">Index</a></li>
 <li><a class="no-num" href="references.html#references">References</a></li>
 <li><a class="no-num" href="acknowledgements.html#acknowledgements">Acknowledgements</a></li></ol><!--end-toc--></body></html>