nowadays, world wide web has become a popular medium to search information, business, trading and so on. various organizations and companies are also employing the web in order to introduce their products or services around the world. therefore e-commerce or electronic commerce is formed. e-commerce is any type of business or commercial transaction that involves the transfer of information acro...

The rapid growth of the World Wide Web (WWW), a distributed hypermedia system implemented on the Internet, has led to simple and widespread access to vast repositories of information. In contrast to much ongoing WWW work that has focussed on access to structured and unstructured data (text, images etc.) repositories, we analyze the problem of accessing repositories of \computable" information (...