THE LARGER INTERNET II TECHNOLOGY ENVIRONMENT Fiber ...

150 CHAPTER 3 The Internet and World Wide Web
Extensible Markup
Language (XML)
a new markup language
specification developed by
the W3C (the World Wide
Web Consortium) that is
designed to describe data
and information
two major browsers — Netscape’s Navigator and Microsoft’s Internet Explorer — have
continuously added features to HTML to enable programmers to further refine their
page layouts. Unfortunately, many of the enhancements only work in one company’s
browser, and this development threatens the attainment of a universal computing
platform. Worse, building browsers with proprietary functionality adds to the costs of
building e-commerce sites. Whenever you build an e-commerce site, special care
must be taken to ensure the pages can be viewed by major browsers, even outdated
versions of browsers.
HTML Web pages can be created with any text editor, such as Notepad or Wordpad,
using Microsoft Word (simply save the Word document as a Web page) or any one
of several Web page editors (See Table 3.7).
XML. Extensible Markup Language (XML) takes Web document formatting a
giant leap forward. XML is a new markup language specification developed by the
W3C (the World Wide Web Consortium). XML is a markup language like HTML, but
it has very different purposes. Whereas the purpose of HTML is to control the “look
and feel” and display of data on the Web page, XML is designed to describe data and
information. For example, consider the sample XML document in Figure 3.19. The
first line in the sample document is the XML declaration, which is always included.
It defines the XML version of the document. In this case, the document conforms to
the 1.0 specification of XML. The next line defines the first element of the document
(the root element): . The next four lines define four child elements of the root
(to, from, heading, and body). The last line defines the end of the root element. Notice
that XML says nothing about how to display the data, or how the text should look on
the screen. HTML is used for information display in combination with XML, which is
used for data description.
TABLE 3.7 HTML TOOLS
SOFTWARE TOOL COMMENTS
Text editor, e.g. Notepad or Wordpad Suitable for creating simple Web pages, text.
PageMill Solid basic page editor.
FrontPage Strong candidate for Web page creation, design,
and site management tools. Good at creating
and integrating graphics and other objects.
DreamWeaver Professional Web page and site development
tool. Good at creating graphics, animations, and
other special effects.