This second edition of Heting Chu's popular work on information representation and retrieval (IRR) features numerous updates and revisions, including coverage of taxonomies, folksonomies, ontologies, social tagging, search/retrieve web service, and next generation OPACs. The chapter on artificial intelligence has been significantly expanded to include a host of related topics such as automatic summarization, question answering, natural language searching, and the semantic web.--Publisher's description.