The Web is causing a revolution in how we represent, retrieve, and process information Its growth has given us a universally accessible database--but in the form of a largely unorganized collection of documents. This is changing, thanks to the simultaneous emergence of new ways of representing data: from within the Web community, XML; and from within the database community, semistructured data. The convergence of these two approaches has rendered them nearly identical. Now, there is a concerted effort to develop effective techniques for retrieving and processing both kinds of...