Abstract: | XML is rapidly becoming a standard for data representation and exchange. It provides a common format for expressing both data structures and contents. As such, it can help in integrating structured, semistructured, and unstructured data over the Web. Still, it is well recognized that XML alone cannot provide a comprehensive solution to the articulated problem of data integration. There are still several challenges to face, including: developing a formal foundation for Web metadata standards; developing techniques and tools for the creation, extraction, and storage of metadata; investigating the area of semantic interoperability frameworks; and developing semantic-based tools for knowledge discovery |