Guest Editors' Introduction: Provenance in Web Applications

The Web has completely changed the way in which we share data, rapidly shifting us from a world of paper documents to a world of digital objects that include online documents, videos, photos, artwork, and databases. This shift has also made data management an increasingly complex problem as applications take advantage of loosely coupled resources brought together by distributed computing systems and abundant storage capacity. It's now easier than ever to modify documents, particularly with the help of general-purpose specifications such as XML, and extract data from documents or databases through the use of technologies such as query languages, REST interfaces, and Web service interconnectivity.