Search Engine Extended Schema for WWW service This is an extended schema for the WWW service which analyze the referrals. It extract the referring sites and it also determines if it was a request from a search engine. The site which reffered that request. This is usually an hostname, but it can also be bookmarks for when the user used a bookmark. The page which referred that request. The name of the search engine, when the request was referred through a search engine. The search phrase used when the request was referred through a search engine.