The first level: according to the nature of the universe, it is divided into humanities books and nature books.
The second level: based on the basic subject attributes of books. Basic humanities subjects: philosophy A, religion B, ethics C, logic D, aesthetics E, psychology F, language G, literature H, art I, politics J, economy K, military L, law M, education N, sports O, media P, information Q, management R, business S, history T, archaeology U, nationality V, life W, wealth X.
Natural basic disciplines: A astronomy, B geography, C mathematics, D physics, E chemistry, F biology, G machinery, H telecommunications, I water conservancy, J electric power, K textile, L food, M architecture, N mine, O metallurgy, P energy, Q transportation, R aerospace, S medicine, T engineering, U agriculture, V forestry, W aquaculture, X computer.
The third level: the division is based on the subject attached to books.
The fourth level: divided by the functional attributes of books (writing, learning, teaching and helping).
The fifth level: books are classified into works (works, theoretical works and applied works), academics (annotation, evaluation, contention, discussion, research, textual research and translation) and teaching (school textbooks, social training textbooks, self-study textbooks, reference materials, handouts, learning materials, popular reading materials, experimental exercises, test questions and exercises, and teaching syllabus) according to the category attributes of books.
Help (dictionaries, encyclopedias, books, political books, yearbooks, manuals, bibliographies, indexes, abstracts, tables, catalogues, standards).
The sixth level: according to the international space of books, it is divided into domestic and foreign original books (non-disciplinary definition space).
The seventh level: according to the time series of books (non-disciplinary time series).
In the edition year, the author's annotation belongs to the business scope of the publishing house and has been annotated in the published books. Repeated labeling in classification numbers will bring a burden to readers. Advocating simplicity is the professional ethics of librarians, which must be resolutely retained, but must be resolutely eliminated. Cancel the recommendation number. Use collection number instead of collection number and book number, and use collection classification number to unify book titles.