Java Tutorial - Java Scipt :

Architectural Considerations

Like the explosion of interconnectivity after the adoption of HTTP, XML is a glue technology that serves as a common data interchange format and facilitates interoperability. With XML, the semantics and metadata are not lost in the encoding of data. XML can be manipulated, transformed, and validated. We continually encounter it with new interoperability technology, such as Web services and document interchange. There’s no doubt that XML has its place in any software architecture and definitely within the J2EE architecture.