Help me analyze the classification and shelving of paper documents in the library.

The paper documents are classified and shelved by seed number. After the documents arrive at the library, the catalogers will classify them into the corresponding categories in the book classification according to the subject attributes of books, periodicals and other documents. Document classification reflects the knowledge category and subject system of book content, and can tell readers what kinds of documents are collected in the library and what books are available in a certain subject or branch of a certain subject. After the documents are classified, the species numbers are assigned in turn according to the similar books. Each book consists of a classification number and a species number, which is also called a call number or a call number. It is not only the basis for our library to organize paper collections, but also the basis for readers to search and find books according to the call number in the stacks and reading rooms.

China Library Classification consists of 5 categories and 22 basic categories (see attached table), each basic category is represented by a capital letter, and each category is subdivided into many subcategories.

I Marxism-Leninism, Mao Zedong Thought and Deng Xiaoping Theory.

Philosophy, religion

Introduction to social science

Politics, law

E military

F economy

G. Culture, science, education and sports

H. Language and writing

I. Literature

J art

History, geography

Introduction to natural science