Information Technology Reference
In-Depth Information
14
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CSS
—Cascading Style Sheets are a major effort to separate content from presentation. Much
more detail about CSS can be found later in this chapter in the section, “Introducing CSS.”
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DOM
—The Document Object Model (DOM) from the World Wide Web Consortium (W3C) offers a
standard structure for web documents. It defines how style sheets, XHTML, and scripts work
together to display a web page. Jeffrey Zeldman has a great analogy in
Designing with Web
Standards
: “If your site were a movie, XHTML would be the screenwriter, CSS would be the art
director (who decides how a film “looks”), scripting languages (like PHP in WordPress) would be
the special effects, and the DOM would be the director who oversees the entire production.”
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HTML 5
—HTML 5 is a newly germinating W3C standard designed to replace both HTML 4 and
XHTML. If it's not the real bridge to XML, it could become the final destination. Find the official
document describing the differences between HTML 4 and 5 at www.w3.org/TR/html5-diff.
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XML
—In its earliest days, Extensible Markup Language (XML) was seen as solving the prob-
lems of HTML by allowing anyone to create their own tagging language for every type of docu-
ment. Although that drive has slowed, XML is now, at least in the web context, leading the way
toward treating tags as ways of defining objects. There is a solid structure behind how web doc-
uments are created. Sir Tim Berners-Lee, the inventor of the Web, believes this will lead to what
he calls the Semantic Web (see the entry later in this list).
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W3C
—The World Wide Web Consortium (W3C) is the governing standards body for HTML and
most web standards on this list.
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OASIS
—The Organization for the Advancement of Structured Information Standards (OASIS)
governs standards mostly related to web services and XML documents of all types. These
include the new XML-based office-productivity standards, such as the Open Document Format,
and two standards for software documentation, DocBook (for printed material) and the Darwin
Information Typing Architecture (DITA) for online documentation.
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Semantic Web
—Berners-Lee defines this as “The Web of data with meaning, in the sense that a
computer program can learn enough about what the data means to process it.” The Semantic
Web is a place where anyone, and any machine, can view the source of a web page and under-
stand both its organization and the type of data it has. The potential to aid human decision mak-
ing in all fields is staggering, if it could be realized (a big “if”).
XML and XHTML
What is XML? Web developers and writers can answer this question in different ways. For
WordPress users, think of XML as a standard that does two things: It completely separates content
from presentation and enforces a structured approach to writing. That structure is defined in one of
two forms: the older Document Type Definition (DTD) or the newer XML Schema. The DTD form is
considered as one type of schema, but the practical differences for those of us who are not informa-
tion architects are few. Both types use the W3C DOM as the basis for the hierarchy. This hierarchy
should remind you strongly of the story outlines we all learned in school.
