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The XML Family
of Technologies
cation on one platform should be able to access and make use of XML data regardless of
how it is stored or formatted thanks to its inherent transformative powers.Tools have
been developed to connect old and new methods of interoperability, linking Z39.50 and
XML, taking cataloguing beyond MARC and on towards Web-compatible material.
Self-describing Objects
Self-describing data items are a fundamental of semantic representation, and facilitate
the continuing increases in automation of Web transactions. In order to be classed as `self-
describing', an object's markup must describe its structure and the data type to which
each element corresponds. XML objects meet these criteria, and when used correctly
XML content should be fully autonomous.The Simple Object Access Protocol (SOAP
assists in the passing of information between different applications in a decentralised and
distributed environment by combining XML and HTTP to send and receive messages.
Rather than dealing in specific application-centred semantics, SOAP works by defining a
simple mechanism for providing a modular packaging model for messages and the
encoding of their contents.Thus SOAP can be used in a large variety of systems, ranging
from instant messaging systems to remote procedure calls (RPCs) initiated by platforms
or operating systems other than that on which the user is working, for example a Linux
server initiating a procedure call on a user's XP machine, which may be useful in devel-
oping large applications that feature multiple programs distributed across a network.
XML and the Web
Because HTML is centred on the presentation of information, as opposed to represent-
ing its structure, it has very limited capabilities to make this information available across
multiple devices and platforms. A user's screen resolution can have a significant impact on
the quality and usability of HTML, with further layout issues arising when handheld PCs
and mobile phones are introduced into the equation.
See for a more detailed account of cross-platform distributed computing using
XML and RPC.
X-SMILES on mobile phone
X-SMILES on iPaq
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