Call Numbers – What They Are & How to Use Them

Call Numbers – What They Are & How to Use Them


A call number is the address of an item on the library shelves. The Eliot D. Pratt Library uses the Library of Congress Classification System (LC) for its collections. LC is subject-based, arranging items by their primary subject.

While there are always some exceptions to the rules, this tutorial will cover what you’re seeing most of the time. Remember, you can always ask the library staff for help understanding or finding items on the shelf.

Here is a brief video on call numbers:

This video was not made by us, so the online catalog and specific locations are different than what you will see, but the basic idea is the same.

Reading Call Numbers – Line by Line

The First Line – General Subject by Letters

LC is broken into 21 general subjects represented by letters. This allows libraries to classify and arrange larger collections by the main subject matter of the text.

A – General Works
B – Philosophy, Psychology, Religion
C – Auxiliary sciences of history
D – World History
EF – History of the Americas
G – Geography, Anthropology, Recreation
H – Social Sciences
J – Political Science
K – Law
L – Education
M – Music and Books on Music
N – Fine Arts
P – Language and Literature
Q – Science
R – Medicine
S – Agriculture
T – Technology
U – Military Science
V – Naval Science
Z – Bibliography. Library Science

LC then breaks into more specific subjects by the addition of 1-2 letters. For the most common LC subject breakdowns, see the list at the bottom of this page or the posters at the end of the stacks in the library.

These are read in alphabetical order, where L comes before LA, which comes before LC, which all comes before M.

The Second Line – Specific Subject by Numbers

LC is hierarchical, using numbers up to four digits in length (1-9999), sometimes with several decimal places, to drill down to the most specific subject. For example:

    • LC call numbers beginning with L deal with Education
    • LC call numbers beginning with LB deal with Theory & Practice of Education
    • LC call numbers in the LB 51-885 range deal with Systems of Individual Educators & Writers
    • LC call numbers in the LB 880-885 range deal with the period 1951-present
    • LC call numbers in LB 880 deal with Educators Outside the US
    • The LC call number for Pedagogy of the Oppressed by Paolo Freire is: LB880.F73 P4313 2002

These are read in simple numerical order, where 7 comes before 70, which comes before 700, which comes before 7000.

The Third Line – Author coded by Letters & Numbers

LC always includes a code representing the author. This part of the call number begins with a decimal and the first letter of the author’s surname followed by numbers representing some of the subsequent letters, for example:

    • Pedagogy of the Oppressed by Paolo Freire is: LB880.F73 P4313 2002

These are read first in alphabetical and then in decimal order, where .O9615 comes before .P9615 and where .P9615comes before .P962

The Fourth Line – Title coded by Letters & Numbers

LC sometimes includes a code representing the title, especially in areas where there may be many titles by the same author. This part of the call number begins with the first letter of the title – excluding A, An, The, etc. – followed by numbers representing some of the subsequent letters, for example:

    • Pedagogy of the Oppressed by Paolo Freire is: LB880.F73 P4313 2002

These are read first in alphabetical and then in decimal order (even though the decimal is usually not present), where O9615 comes before P9615 and where P9615 comes before P962

The Fifth Line – Year of Publication

LC usually includes a year of publication. This is almost always present on newer titles, but sometimes absent on older materials

    • Pedagogy of the Oppressed by Paolo Freire is: LB880.F73 P4313 2002

These are read by oldest to newest, where LB880.F73 P4313 comes before LB880.F73 P4313 1993, which comes before LB880.F73 P4313 2002

Other Lines – Locations, copies, volumes, etc.

Information that precedes the LC Call Number is included by the library to help you find what you’re looking for when items are not shelved in the main collection with the bulk of our print books. For instance, we’ll add something like DVD before the call number if it’s a video or REF if it’s a Reference item.

Information that follows the LC Call Number can vary. It may be volume, issue, or copy number to let you find the exact item you’re looking for without having to pull it off the shelf. It may also be location information, like Special Collection, to let you know it’s not shelved with the main collection.

Reading Call Numbers – All Together Now!

Call numbers are read from left to right and from top to bottom. In the catalog, a call number is written out all on one line but on the item it is displayed in a column, as below. This is so it will fit on the item’s spine whenever possible and be visible when shelved. This is called a spine label. Call numbers are read the same way whether they’re all on one line or in a column. For example:

One line, as in the catalog: LB880.F73 P4313 2002

In a column, as on a spine label:

copy 5

Always remember to note the location and availability of an item before you go looking for it. If an item is checked out, missing, or on display, the catalog will tell you so under the item record.

Library of Congress Classification System

This is a basic outline of the LC General Subjects. For a more specific list, check out the Library of Congress Classification Outline. This may be helpful in cases where further breakdown of subjects, for instance by time period, is not obvious and you want to be able to browse more efficiently.

Primary Class:
A | B | C | D | E-F | G | H | J | K | L | M |
N | P | Q | R | S | T | U | V | Z |


General Works

AC Collections. Series. Collected Works
AE Encyclopedias
AG Dictionaries and other general reference works
AI Indexes
AM Museums. Collectors and collecting
AN Newspapers
AP Periodicals
AS Academics and learned societies
AY Yearbooks. Almanacs. Directories
AZ History of scholarship and learning. The humanities


Philosophy, Psychology, Religion

B Philosophy (General)
BC Logic
BD Speculative philosophy
BF Psychology
BH Aesthetics
BJ Ethics
BL Religions. Mythology. Rationalism
BM Judaism
BP Islam. Bahaism. Theosophy, etc.
BQ Buddhism
BR Christianity
BS The Bible
BT Doctrinal Theology
BV Practical Theology
BX Christian Denominations


Auxiliary sciences of History

C Auxiliary sciences of history (General)
CB History of Civilization
CC Archaeology
CD Diplomatics. Archives. Seals
CE Technical chronology. Calendar
CJ Numismatics
CN Inscriptions. Epigraphy
CR Heraldry
CS Genealogy
CT Biography


World History

D History
DA Great Britain
DAW Central Europe
DB Austria – Liechtenstein – Hungary – Czechoslovakia
DC France – Andorra – Monaco
DD Germany
DE Greco-Roman World
DF Greece
DG Italy – Malta
DH Low Countries – Benelux Countries
DJ Netherlands (Holland)
DJK Eastern Europe (General)
DK Russia. Soviet Union. Former Soviet Republics – Poland
DL Northern Europe. Scandinavia
DP Spain – Portugal
DQ Switzerland
DR Balkan Peninsula
DS Asia
DT Africa
DU Oceania (South Seas)
DX Gypsies


History of the Americas

E 11-143 America
E 151-889 United States
F 1-975 United States local history
F 1001-1145.2 British America (including Canada). Dutch America
F 1170 French America
F 1201-3799 Latin America. Spanish America


Geography, Anthropology, Recreation

G Geography (General). Atlases. Maps
GA Mathematical geography. Cartography
GB Physical geography
GC Oceanography
GF Human ecology. Anthropogeography
GN Anthropology
GR Folklore
GT Manners and customs (General)
GV Recreation. Leisure


Social Sciences

H Social Sciences (General)
HA Statistics
HB Economic theory. Demography
HC-HD Economic history and conditions
HE Transportation and communications
HF Commerce
HG Finance
HJ Public Finance
HM Sociology (General and Theoretical)
HN Social history. Social problems. Social reform
HQ The family. Marriage. Women
HS Societies: Secret, benevolent, etc.
HT Communities. Classes. Races.
HV Social Pathology. Social and public welfare. Criminology
HX Socialism. Communism. Anarchism


Political Science

J General legislative and executive papers
JA Political science (General)
JC Political theory
JF Political institutions and public administration
JJ Political institutions and public administration (North America)
JK Political institutions and public administration (United States)
JL Political institutions and public administration (Canada, Latin America, etc.)
JN Political institutions and public administration (Europe)
JQ Political institutions and public administration (Asia, Africa, Australia, Pacific Area, etc.)
JS Local government. Municipal government
JV Colonies and colonization. Emigration and immigration. International migration
JX (obsolete) International Law, see JZ and KZ
JZ International relations



K Law in general. Comparative and uniform law. Jurisprudence
KB Religious laws in general. Comparative religious law. Jurisprudence
KBM Jewish law
KBP Islamic law
KBR History of canon law
KBS Canon law of Eastern churches
KBU Law of the Roman Catholic Church. The Holy See
KD-KDK United Kingdom and Ireland
KDZ America. North America
KE Canada
KF United States
KG Latin America – Mexico and Central America – West indies. Caribbean area
KH south America
KJ-KKZ Europe
KL-KWX Asia and Eurasia, Africa, Pacific Area, and Antarctica
KZ Law of nations



L Education (General)
LA History of education
LB Theory and practice of education
LC Special aspects of education
LD Individual institutions – United States
LE Individual institutions – America (except United States)
LF Individual institutions – Europe
LG Individual institutions – Asia, Africa, Indian Ocean islands, Australia, New Zealand, Pacific Islands
LH College and school magazines and papers
LJ Student fraternities and societies, United States
LT Textbooks


Music and Books on Music

M Music
ML Literature of music
MT Musical instruction and study


Fine Arts

N Visual Arts
NA Architecture
NB Sculpture
NC Drawing. Design. Illustration
ND Painting
NE Print media
NK Decorative arts
NX Arts in general


Language and Literature

P Philology. Linguistics
PA Greek language and literature. Latin language and literature
PB Modern languages. Celtic languages
PC Romanic languages
PD Germanic languages. Scandinavian languages
PE English language
PF West Germanic languages
PG Slavic languages. Baltic languages. Albanian language
PH Uralic languages. Basque language
PJ Oriental languages and literatures
PK Indo-Iranian languages and literatures
PL Languages and literatures of Eastern Asia, Africa, Oceania
PM Hyperborean, Indian, and artificial languages
PN Literature (General)
PQ French literature – Italian literature – Spanish literature – Portugese literature
PR English literature
PS American literature
PT German literature – Dutch literature – Flemish literature since 1830 Afrikaans literature – Scandinavian literature – Old Norse literature: Old Icelandic and Old Norwegian – Modern Icelandic literature – Faroese literature – Danish literature – Norwegian literature – Swedish literature
PZ Fiction and juvenile belles lettres



Q Science (General)
QA Mathematics
QB Astronomy
QC Physics
QD Chemistry
QE Geology
QH Natural history – Biology
QK Botany
QL Zoology
QM Human anatomy
QP Physiology
QR Microbiology



R Medicine (General)
RA Public aspects of medicine
RB Pathology
RC Internal medicine
RD Surgery
RE Ophthalmology
RF Otorhinolaryngology
RG Gynecology and obstetrics
RJ Pediatrics
RK Dentistry
RL Dermatology
RM Therapeutics. Pharmacology
RS Pharmacy and materia medica
RT Nursing
RV Botanic, Thomsonian, and eclectic medicine
RX Homeopathy
RZ Other systems of medicine



S Agriculture (General)
SB Plant culture
SD Forestry
SF Animal culture
SH Aquaculture. Fisheries. Angling
SK Hunting sports



T Technology (General)
TA Engineering (General). Civil engineering
TC Hydraulic engineering. Ocean engineering
TD Environmental technology. Sanitary engineering
TE Highway engineering. Roads and pavements
TF Railroad engineering and operation
TG Bridge engineering
TH Building construction
TJ Mechanical engineering and machinery
TK Electrical engineering. Electronics. Nuclear engineering
TL Motor vehicles. Aeronautics. Astronautics
TN Mining engineering. Metallurgy
TP Chemical technology
TR Photography
TS Manufactures
TT Handicrafts. Arts and crafts
TX Home economics. Cookbooks


Military Science

U Military science (General)
UA Armies: Organization, description, military situation
UB Military administration
UC Maintenance and transportation
UD Infantry
UE Cavalry. Armor
UF Artillery
UG Military Engineering. Air forces
UH Other services


Naval Science

V Naval science (General)
VA Navies: Organization, description, naval situation
VB Naval administration
VC Naval maintenance
VD Naval seamen
VE Marines
VF Naval ordinance
VG Minor services of the navies
VK Navigation. Merchant marine
VM Naval architecture. Shipbuilding. Marine engineering


Bibliography. Library Science. Information Resources (General)

Z Books (General). Writing. Paleography. Book industries and trade. Libraries. Bibliography
ZA Information resources (General)