A Study About Search Engine And Its Ranking Algorithms

This article gives an introduction to the mechanism of search engine and the theory about the ranking algorithm of relevance. It analyzes the structure and mechanism of search engine from the aspect of the classic theory of information retrieval system. It explicates and lucubrates all parts of search engine. It divides its development history into four phases by the transformation of the emphasis in the ranking algorithm. The four phases are the phase of Boolean modeK the phase of vector modeK the phase of hypertext link analysis and the phase 6f priority by payment. It details the development of search engine and analyze the theory of ranking algorithm in every phase. It analyzes and evaluate the advantage and disadvantage of each theory and summarize the cause which improves the ranking theory continuously.