How many book classifications are there in the world?

I. Classification of books in the Library of Congress:

A- general category B- philosophy, psychology, religion C- history and related sciences General introduction D- world history (except American history) E and F- American history G- geography, anthropology, leisure H- social science J- politics K- law L- pedagogy M- music N- art P- language and literature Q- science R- medicine S- agriculture T- technology U- military.

Second, Dewey decimal book classification:

Dewey decimal book classification was first published in 1876. After 22 major revisions, the content has been revised and expanded to a considerable extent. The latest edition is the 2004 edition. This classification uses three digits to indicate the classification code, and * * * can be divided into 10, 100 and 1000. In addition to the three-digit classification, there are generally two additional codes to indicate the discussion of different regions, time, materials or other characteristics. The classification code and the additional codes are separated by a decimal point ".". For example, 330 table economics +.9 table difference discussion +.04 table Europe = 330.94 table European economics.

Three, China book classification:

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