O标引语言(ILS)的功能定义标引语言是图书馆员(文献工作专家/情报人员)和文献用户之间进行文献主题信息交流的手段。图书馆根据所选定的标引语言对文献进行标引(赋与主题标识)以便于用户或图书馆员用来进行检索。我们寄希望于用户具有丰富的标引语言知识是不妥的。因此,对于大多数标引语言和情报检索系统来说,都应从用户自然语言词汇中选取款 O Definition of ILS Functional Citation Language is the means by which librarians (bibliographers / intelligence personnel) and subject users exchange information on thematic topics. The library indexes (assigns a subject ID) to the literature based on the selected indexing language for retrieval by users or librarians. We hope that users have a wealth of knowledge of the indexing language is not proper. Therefore, for most indexing languages ​​and information retrieval systems, the user’s natural language vocabulary should be selected