If you are looking (36) information, library shelves are a good place (37) .But if you need up-to-the-minute data or have specialized needs, you may (38) a computerized database more useful, (39) expensive, and less time consuming.A、database, a file of (40) on one subject or family of subjects, can be (41) and maintained in a computer’s memory. The speed of the computer then enables you (42) any item in this file almost instantly. The three main types of databases are statistics, bibliographies, and full text. Statistical databases store vast (43) of numerical data, such as wage and price indexes, census information, foreign exchange rates, and bond prices, bibliographic databases store references and (44) of articles (45) periodicals and newspapers. Full-text databases offer the complete texts of such materials (46) newspaper, magazine and journal articles. (47) databases exist today, and their numbers are (48) . Many companies have their (49) database, (50) is accessible (51) employees through computer terminals or microcomputers. (52) addition, several hundred commercial data bases are now available (53) the public, (54) literally millions of information readily retrievable. These databases cover specific fields, such as law and financial (55) , or general information, such as sports and weather datA、 A．for B．by C．in D．as
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