x-height measurement, using with CSS1, 292
XForms, rise of, 402-403
XHTML 1.0 frameset DTD, code for, 878-898
XHTML 1.0 strict DTD, code for, 862-878
XHTML 1.0 transitional DTD, example of, 55-56, 842-862
XHTML 1.1 specification Web address, 578
XHTML Basic specification Web address, 578
XHTML documents
adding styles to, 270-271
forming valid types of, 22
hiding script markup in, 438-439
including scripts in, 436-445
including VBScript in, 435-436
sample tree structure of, 285-286
specifying scripting languages for, 440
structure and inheritance of, 284-288
using event handler attributes with, 441-445
using linked scripts with, 441
validating, 45-46
XHTML (Extensible Hypertext Markup Language)
case sensitivity of, 19-20
combining with XML, 561-565
content model of, 20
development of, 8
DTD syntax for, 10-11
enforcing rules for, 22-23
events defined in, 442-443
versus HTML 4, 5-6
impact on public Web, 26
myths about, 25-26
table specifications defined for, 222-223
Web address, 577-579
XML application languages
RSS (Really Simple Syndication), 572-573
SOAP (Simple Object Access Protocol), 570-572
SVG (Scalable Vector Graphics), 569-570
WML (Wireless Markup Language), 565-568
XML Data Islands in Internet Explorer, overview of, 563-565
XML documents, displaying with CSS, 560-561
XML (Extensible Markup Language). See also valid XML; well-formed XML
combining with XHTML, 561-565
displaying, 555-561
importance of, 547
as meta-language, 549
predicting future of, 573-574
relationship to HTML, 8
rules for, 550-551
and SGML, 548-549
transforming to HTML, 555-560
Web address for, 565
XML keywords, overview of, 840
<xml> (XML Data Island) element, overview of, 563-565, 732-733
xmlns attribute, example of, 561
<xmp> (example) element, overview of, 734
XSL
transforming XML to HTML with, 555-560
Web address for, 560
XSL style sheet, example of, 558-559
XSLT (eXtensible Style Sheet Transformations), purpose of, 555