SAN JOSE, California -� What's the best method for transforming the Web from a collection of electronic documents into a smart information-delivery service?
It's one of the fundamental questions driving the work of Web developers meeting in San Jose, California, this week to advance the eXtensible markup language, known as XML.
Devotees and developers see XML as the mainstay for improving a well-worn, but still very useful, human construct: the document. They're slowly winning converts.
"Documents are still very much with us," said Jon Bosak, chairman of the World Wide Web Consortium's XML coordination group, who's considered by many the father of XML. "They haven't really changed much in 5,000 years, in general. People like to do some very basic things using documents. That doesn't change just because they're electronic."
Bosak addressed the state of the markup language in his opening plenary speech at XTech '99 Tuesday, a conference pulling together XML creators, users, and software companies seeking to build support for the spec into their products.
"You have to be able exchange [documents], you have to be able to read them, and you have to know what they mean," Bosak said. It is hoped that XML will eventually refine those elements in the increasing variety of devices that display them, from PalmPilots to TV-based Web browsers.
XML is founded on electronic-document concepts originally developed by hypertext pioneer Ted Nelson in the 1960s. "It will bring linking on the Web into the 1970s," said Bill Smith, chairman of the hyperlink working group at W3C, speaking at the conference. "This is something that's been around for a long time."
XML is intended to take Web pages beyond the basic display capabilities of HTML and transform documents into contextual objects that can perform more useful electronic feats. It goes further than HTML, which focuses on the display of text and graphics, to provide telling information about the data. HTML uses a finite list of tags that have been approved by a standards body, while XML is extensible, letting authors create their own descriptive tags.
For example, an XML tag dubbed "address" might indicate that the text that follows it is a street address, for example. Similarly, XML could tag information as the lead paragraph in body text, pictures, or news headlines.
"It's a metalanguage for defining tag languages -- a system where you can define a language by whatever problem you've got," Bosak said.
If XML becomes the universal format for structuring data, as its backers anticipate, everything from classified ads to news articles to recipes to search engines will be more orderly, and applications like browsers can manipulate and display these documents in more useful ways, according to XML advocates.
