Using HTML, XML, and XHTML

HTML (Hypertext Markup Language) is the fundamental language of the Web. It defines a set of embedded instructions, called tags that control how information is displayed in a browser, and how the browser is to react to certain events. For instance, the <hl> and </hl> tags mark the beginning and end of a first-level heading, which even the most rudimentary browser can render in a large, bold headline font. Because HTML files are composed of plain text, they are ideal for sharing across otherwise incompatible computer platforms.

HTML is the basic (some would say "old") technology that drives the Web: Any browser will support early versions of HTML, and most HTML pages based on the classic (read: "old") tags will display perfectly well in any browser. But like so many other components of the Web, HTML has evolved on Web time, mutating so quickly that it's difficult to keep track of the various standards from day to day.

Office applications take advantage of many Extensible Markup Language (XML) tags, which go well beyond the capability of standard HTML to describe and present data. Using XML, a developer can create custom tags that define any sort of data or formatting, for use on the Web and elsewhere. Whereas HTML is based on standard tags defined by the World Wide Web Consortium (W3C), XML tags can be highly customized so that they precisely fit the needs of the developer; collections of XML tags can in turn be shared as schemas.

Today, the integration of XML and HTML has resulted in a successor to plain-vanilla HTML called Extensible HyperText Markup Language (XHTML). Most sophisticated Web developers use XHTML to create the complex, interactive pages you see on the Web. Similarly, most advanced Office features rely on XHTML to help documents survive the round-trip between the application that created them and the browser.

Questionnaire:

• Explain about the use of HTML, XML, and XHTML in MS Office.