Reference tools are mainly used to retrieve all kinds of facts and data, and the result is a direct and valuable answer. In fact and data retrieval, various reference tools are used, including dictionaries, dictionaries, encyclopedias, yearbooks, handbooks, catalogues, tables and their corresponding CDs and database systems. Strictly speaking, reference tools can be special retrieval tools. The use of reference tools is generally attached to the front of the reference tools. Generally, it can be easily used by sorting methods such as classification, subject method, phonetic sequence method, radical method and time sequence method. According to different classification methods, there are several types of retrieval tools: ① Manual retrieval tools, including directories, indexes, abstracts, etc. ② Computer retrieval tools, including databases and search engines. Classification by publication form: ① Book retrieval tools ② Card retrieval tools ③ Micro retrieval tools ④ Machine-readable retrieval tools ④ Classification by collection scope: ① Comprehensive retrieval tools ② Professional retrieval tools ③ Individual retrieval tools are classified by description form: ① Catalogue, ② Index and ③ Abstract. Explain. Since it is an information retrieval course, we should learn this course well. In the information age, I believe your teacher will teach you how to use search tools, such as how to use search engines such as Baidu and Google. How to use VIP, cnki and other databases; How to use online library resources such as Superstar Digital Library? You can keep asking questions until you are satisfied! Have fun studying!