Two emerging technologies known as XML (Extensible Markup Language) and RDF (Resource Description Framework) promise to transform the way information gets published on the Web.

XML and RDF are setting the stage for a next-generation Web that promises to be easier to navigate, more automated and readily accessible from a wide array of devices including mobile phones and handheld computers.

Show stealers XML and RDF are the main attractions at the Ninth International World Wide Web Conference (WWW9) being held this week. More than 1,400 Web application developers and Web site designers are attending the conference, which is the premier event of the year for showcasing cutting-edge Web technologies.

"There's no question that XML is ready for the real world," says Albert Vezza, co-chair of the WWW9 conference and president of Foretek Seminars in Reston, Virginia. "XML grew out of nothing at the last conference, and it is still pretty big this year. It is clearly what the attendees are most interested in."

RDF, meanwhile, is new to the conference schedule this year. The details about RDF aren't "totally worked out yet, but it's a hot topic".

The World Wide Web Consortium (W3C) developed XML and RDF. W3C sponsors a track at the WWW9 conference.

Mass appeal XML is a simple, flexible text format designed for large-scale electronic publishing. It provides a universal format for marking up different kinds of structured data on the Web including documents, graphics, mathematical equations and multimedia. XML is used to transmit information between Web applications, and it supports automatic processing across the Web.

XML became a recommended specification in February 1998, but the W3C continues to roll out related technologies such as style sheets, query languages and schema. Many XML-compliant products are already shipping, particularly in the area of e-commerce applications.

The newer development is RDF, which provides a layer of metadata – a description of the data – on top of the information marked up in XML. Because RDF enables automated processing of metadata, it promises to improve search engine capability, support intelligent software agents, and create new ways of cataloguing information for improved navigation.

On the up The RDF model and syntax became a recommended specification in February of 1999, but the schema is still in candidate mode. Early applications of RDF such as the Netscape Communications' Netscape 6 browser and the epinions.com Web site are just starting to hit the market.

When taken together, XML and RDF offer significant advantages to corporate IT managers, according to Eric Miller, a senior research scientist at the Online Computer Library Center. Miller is co-ordinating Developers' Day at the WWW9 conference, which is being held on Friday.