Search engine is roughly composed of three parts: search system, indexing system, and retrieval system. The so-called search engine is a retrieval technology that uses specific strategies to retrieve information from the Internet and feeds it back to users based on user needs and a certain algorithm.
The working process of a search engine is generally divided into five steps:
(1) Crawl web pages from the Internet, using web spider programs that can automatically collect web pages from the Internet , automatically access the Internet, and crawl to other web pages along all URLs in any web page, repeat this process, and collect all crawled web pages back.
(2) The web page analysis program analyzes the collected web pages, extracts relevant web page information, and performs a large number of complex calculations based on a certain correlation algorithm to obtain the results of each web page for each page content and hyperlink. The relevance of a keyword.
(3) Then use this relevant information to build a web page index database.
(4) The user inputs query conditions through the query interface, and the retrieval program searches in the index database and finds all relevant web pages that match the keyword from the web page index database.
(5) The page generation system organizes the link address and summary of the search results and returns them to the user.
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