Theoretical library science is a subject that studies the general principles of library science. It provides basic theories and research methods for the whole library science, describes the general situation of the whole library development, and plays a guiding role in other components and related parts of library science.
Theoretical library science is a deepening field. Judging from the historical and realistic research results, it has the following branches.
The basic theoretical research of library science mainly discusses the definition, research object and content, theoretical basis, system and structure of library science, branches and related disciplines of library science, methodology of library science, nature, social function and role of library, and library and social progress.
The research of library construction includes development law, experience and lessons, organization principle, system, library network type and establishment principle, library legislation, librarian training, organizing academic research of library science, and library development strategy research.
The great library science is a branch subject that makes macro exploration and gradually forms the research object of library science. It studies the relationship between library and society, the relationship with document information system, the family relationship in library cause (including the relationship between libraries) and so on.
Comparative library science uses comparative research methods to study library problems in different countries, regions and cultural backgrounds. Through comparison, the similarities and differences between them are determined, the reasons are analyzed and explained, and the conclusion that can reveal the objective law is drawn.
Under the guidance of the basic theory provided by theoretical library science, practical library science is a big category formed by studying the theories, methods and technologies of library's specific work, including library work rules, library management, library modernization and other practical work fields.