Search engines do not index the entire web
{"Image DocumentName": "Search engines do not index the entire web", "Image ImageDescription": "550 billion web documents July 2000 (BrightPlanet) Google indexed 1 billion sites : surface web; 167 terabytes. 2001: deep web: 91,000 terabytes (545 times more) Deep web content is estimated at 500 times that of surface web (British Library) Top search engines cover less than 50% of the Web (Nature 1999) 85% of total information about people, technologies and companies not indexed by search engines (Estelle Metayer 2008)", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}