Search engine is an information resource on the Internet search collation and classification, and stored in the network for users to query the database platform does not generate its own content. The purpose of a user searches for information to solve practical problems. The initial stage of development in the network, less the amount of information, the user can only be used to find information portal, the portal site as a result of the classification, but with the network era of information explosion, to facilitate the emergence of search engine users to find information.