The result of keyword searching is imprecise and inconsistent. Unless used in a deliverily restricted way HTML is not useful for structured data queries. However, this method also uses keywords to interpret the content and needs a human to view the pages. Soumen Chakrabarti, Byron E. Dom, S. Ravi Kumar, Prabhakar Raghavan, Sridhar Rajagopalan, Andrew Tomkins, and David Gibson andJon Kleinberg. Mining the web's link structure .
Hyperlinks contain high quality semantic clues to a page s topic.
A hyperlink to a Web page represents an implicit endorsement of the page being pointed to. Keywords can be extracted from fulltext documents or metatags. The title tag, which is only valid in a head section, defines the title of an HTML document. Authorities and hubs are given top ranks of the search results. An initial query is usually a wild guess.