As a data representation language, eXtensible Markup Language (XML) needs to satisfy new requirements from the rapid development of Peer-to-Peer architectures and wide use of Web Services. The solution of this problem is the proposal of Intensional XML Data, such as Active XML (AXML). AXML consists of normal XML data and embedded Web Service calls. This extension of XML promises many advantages such as: (1) reusable data, (2) dynamic and fresh data, (3) user-oriented and intensive data, (4) time and bandwidth saving, (5) Web Service invocations simplifications, (6) sharing computing tasks as well as (7) support for distributed computing.
This chapter focuses on the introduction of intensional XML data, a new extension for XML that is able to integrate XML data and Web Services. Moreover, a current solution for intensional XML that is known as Active XML (AXML) will be introduced and discussed. Advantages of the new XML extension and its comparison to traditional XML will be presented through examples.