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The XML Family
of Technologies
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The Extensible Stylesheet Language Transformations language (XSLT, sometimes also called
the Extensible Stylesheet Language Template) is designed for use as part of XSL (see above),
although it may also be used independently.
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In addition to XSLT, XSL includes a
vocabulary for specifying the format of XML documents. XSL describes how such docu-
ments are transformed into other XML documents that use the same formatting vocabulary.
Due to its newness, it is estimated that around half of all Web users are unable to access
all XSLT transformed XML, as they do not have a recent enough browser. However, it is
possible to use the PHP Hypertext Preprocessor language (PHP), or another compliant
scripting language such as ASP, ASP+, JSP, JSP+, to transform the XML on the server
side, thus delivering more widely compatible XHTML in its place.
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Web services are self-
contained, self-describing,
modular applications that
can be published, located,
and invoked across the Web.
A Web service performs a
function, which can be any-
thing from a simple request
to a complicated business
process. Once a Web service
is deployed, other applica-
tions and other Web services
can discover and invoke it.
The Universal Description,
Discovery and Integration (UDDI) protocol is a kind of directory of Web services which
creates a standard, interoperable platform enabling users (and other applications) to find
and make use of Web services over the Net, `quickly, easily, and dynamically'.
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XML and Other Media
Although XML was designed with online delivery in mind, its uses are by no means
confined to the Web. XML has applications in the Wireless Application Protocol (WAP)
and the Wireless Markup Language (WML) for mobile devices, as well as in printed
media.
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Applications such as Logictran's RTF converter
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can be used to transform docu-
ments from Rich Text Format to XML, thus allowing them to be delivered and present-
ed in a number of different ways.
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Bearing in mind that XML is both a human-readable
and a machine-readable technology, it should be clear that print and other such legacy
media stand to benefit from the XML treatment as well as digital material.Working prac-
tices and internal/external communications have much to gain from the change in
thinking that XML has brought into being.
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http://www.w3.org/TR/xslt
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http://www.w3.org/TR/xhtml1/. XHTML is like ordinary HTML, but much more strictly governed. Of
course, a dedicated XSLT processor such as SAXON could be used instead for a more direct approach to
such a problem.
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http://www.uddi.org/about.html. See also DigiCULT.Info 3 for more on UDDI and Web Services in general.
54
See the section on Mobile Access to Cultural Information Resources below.
55
http://www.logictran.net/products/
56
CDocS: http://committees.gla.ac.uk/cdocs/; Logictran: http://www.logictran.com/.
Univ
ersity of Glasgow
The relationship between XML, scripting language, client and server
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