识别属性和关联实体是RDA的两大核心内容。文章从编目史学角度出发,阐明关系描述对于实现目录“导航”功能的重要性,进而阐述RDA对传统编目规则中关系描述的继承与发展。重点解读RDA中“关系”的构成和“关系”的类型,进而分析这些关系的实质以及在RDA中的体现,介绍RDA各种主要“关系”在MARC21机读目录格式中的表达方法。 Identifying attributes and associated entities are two core components of RDA. From the perspective of cataloging history, the article illustrates the importance of relationship description for realizing the function of directory “navigation ”, and then elaborates the inheritance and development of relationship description by RDA in traditional cataloging rules. It focuses on the composition of “relationship ” and the type of “relationship ” in RDA, and then analyzes the essence of these relationships and their manifestation in RDA. It introduces the main “relationship” of RDA in the MARC21 MRTD format The expression method.