XML is a metalanguage that defines a new technology in the development of the Internet. It is designed to simplify the transmission of structured documents over the Web. This paper is a short overview of XML, and it focuses on XML’s role in networked business applications. The paper is structured in eight sections.

Section 1 is an introduction to XML technology. It describes XML as a new technology, which improves the behavior of data across networks. Section 2 compares XML to HTML. It clarifies that XML is not a replacement for HTML because the two languages are companions. Section 3 deals with the formal definition of an XML document, based on the document type definition.

Section 4 presents XSL, a transformation language that acts on original XML data and transforms it into other sets of data, such as HTML. XSL is presented as a bridge between internal data structure and external output.

Section 5 focuses on XML as a core technology in the business world, because it is deployed over an existing infrastructure (Internet and intranet). Section 6 presents XML’s role in e-commerce, specifically in micropayment systems. Section 7 deals with XML-encoded advertisements, which can contain meta-information in addition to a physical representation of the ad’s content.

Section 8 contains concluding remarks.

The paper includes a long list of useful Web addresses, which present more specific and complete information about XML. The length of the presentation is just right, allowing a rapid assimilation of important principles. The paper fulfills its basic purpose as an informative source about XML technology and XML’s business role.