Collection management is one of the core tasks of the library. The life cycle of collection management can be summarized as collection resource planning, document resource procurement, processing, disclosure, evaluation and elimination. Among them, collection disclosure is the central link in the life cycle of collection management, which not only connects other links of collection management, but also serves as a bridge between "collection" and "use" of the library.

Specifically, the collection itself is divided into paper collection and electronic collection (digital collection).

The traditional library is mainly based on paper collections, and the research and technology on paper collections disclosure are also very mature. It is recorded by MARC and searched by users through OPAC. For example, in any library, use OPAC retrieval system to input information such as book title, ISBN and author. , you can find out whether the relevant books are collected by the library.

With the development of information technology, the proportion of digital resources in libraries is increasing, and the collection resources of libraries have rapidly developed to pay equal attention to paper resources and digital resources. The purchasing funds of digital resources in many libraries have far exceeded those of paper resources. With regard to the disclosure of digital resources, relevant technologies and standards are not yet perfect. At present, the main mode is to open digital resources through the "database navigation page", enter the database page of the library, and search or browse the database through "subject", "subject" and "name" to know which digital resources the library has purchased.