| In the following sections we explore details of XML as it is applied to vertical industry segments, horizontal cross-industry applications, and Web-based distributed computing. As an aid to understanding the various initiatives launched by XML, it's useful to view the application of XML as occurring in three waves. Figure 3-1 illustrates the characteristics of these waves as they move XML from a vertical industry vocabulary language to vocabularies that add aspects of configuration and action, while adding instructions as data to the XML mix. Finally we see XML's simple design and ability to combine with other technologies as the springboard that takes XML into the new dimensions of distributed computing and XML protocols. For each of these categories, we explore several concrete examples of XML in practice, pointing out along the way details of how designers use elements and attributes to build XML vocabularies. |