This is a very brief outline of how books are organized by subject using the Library of Congress Classification system.
A-AZ General Works - Encyclopedias, almanacs, general indexes
B-BX Philosophy, Psychology, Religion
- BD Philosophy
- BF Psychology
- BL-BX Religion
C-CT Auxiliary Sciences of History
- CC Archaeology
- CS Genealogy
- CT Biography
D-DX General and Old World History
Includes geography and descriptions of regions and countries
- DA-DR Europe
- DK Soviet Union
- DS Asia
- DT Africa
E-F History: Americas
- E North American
- F United States local history, Latin America
G-GV Geography, Anthropology, Recreation
- G Geography, atlases
- GE Environmental sciences
- GN Anthropology
- GR Folklore
- GV Sports, dance, games
H-HX Social Sciences
- H General social sciences
- HA Statistics
- HB Economics
- HC Economic conditions
- HD Industry, labor
- HE Transportation, communication
- HF Business, commerce
- HG Finance
- HM Sociology
- HQ Family, marriage, aged, women, sexuality
- HT Communities, cities, races
- HV Criminology, drug abuse
- HX Socialism, communism, anarchism, utopias
J Political Science
- JF Constitutional history
- JK United States
- JS Local government
- JX International law, world peace
K Law
- KF United States law
- KFN North Carolina law
L Education
M Music
N-NX Art
- NA Architecture
- NB Sculpture
- NC Drawing, design, illustration
- ND Painting
- NK Arts, crafts
P-PZ Language and Literature
- P Philology, linguistics, communication
- PE English dictionaries, thesauri
- PN Drama, poetry, radio broadcasts, movies, television, journalism
- PQ Romance literature
- PR English literature
- PS American literature
- PZ Fiction in English
Q-QR Science
- Q General science
- QA Mathematics, computer science
- QB Astronomy
- QC Physics
- QD Chemistry, biochemistry
- QE Geology
- QH Natural history
- QK Botany
- QM Human anatomy
R Medicine
- RA Public aspects of medicine
- RC Practice of medicine
- RM Therapeutics, drugs
- RT Nursing
S-SK Agriculture
- SB Plant culture
- SD Forestry
- SK Hunting sports
T-TX Technology
- TA Engineering
- TL Motor vehicles, aeronautics
- TR Photography
- TX Home economics
U Military Science
V Naval Science
Z Bibliography, library science
