A Declarative Language for Querying and Restructuring the WEB

World Wide Web is a hypertext based, distributed information system that provides access to vast amounts of information in the internet. A fundamental problem with the Web is the diiculty of retrieving speciic information of our interest, from the enormous number of resources that are available. In this paper, we develop a simple logic called WebLog that is capable of retrieving information from HTML (Hypertext Markup Language) documents in the Web. WebLog is inspired by SchemaLog, a logic for multidatabase interoperability. We demonstrate the suitability of WebLog for (a) querying and restructuring Web information, (b) exploiting partial knowledge users might have on the information being queried, and (c) dealing with the dynamic nature of information in the Web. We illustrate the simplicity and power of WebLog using a variety of applications involving real-life information in the Web.