Not enough information on the Web for you? Well, you haven't seen the half of it. According to BrightPlanet, a search-tools technology company, the amount of content on the Web is roughly 500 times what people generally believe. What the company calls the deep Web might contain as much as 7500TB of information in 550 billion Web pages, compared with the 19TB of information in the 1 billion Web pages estimated to make up the surface Web (i.e., the part of the Web that mainstream search engines such as Google and AltaVista can index). The additional information is in specialized, searchable databases with interfaces that serve up Web pages on the fly. What are we missing? Graph 2 shows BrightPlanet's estimates of deep Web content by type.
