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Get Started @ HKUST Library: Call numbers - Classification


This page give broef information about how material is arranged at HKUST Library.

 Go to the whole Classification of Material in the Library for to lean more in detail.

Call number = Classification Number

A call number can be a random number, but in modern libraries the call number is a classification number.

LC (Library of Congress) Classification System:  Used by HKUST Library!

It was created by the Library or Congress in the USA. Most university and research libraries in North America use it. Here is an outline of the LC Classification from the LC's own home page.  Here's a link to the detailed lists.

Classification numbers are built in Dewey, they are assigned in LC.

Both systems try to bring together similar items.The similarity is based on the following criteria:

  1. "What it's about?" - subject
  2. "Who wrote (composed, acted, etc.) it?" - author
  3. "What's it called?" - title

You may already be familiar with the Dewey Classification System, it's used in Hong Kong public libraries and in most school libraries, and in some other universities in Hong Kong. An outline of Dewey Classification categories is available from OCLC.

Basic Classification Number Anatomy & Creation

Example A

QR  Microbiology 
370  Virology (QR355->QR502)
.O75  Title of book (Origin and Evolution of Viruses)
1999  Publication Year

Example B

DS  Asian history
796  Chinese History (DS701-> DS799.99)
.H75  Hong Kong History (social & intellectual aspects) (DS796.H75)
W55  Author's name (Wiltshire)
1991  Year of publication

Why is there an an alphanumeric combination for title in Example A, but for author in Example B?

Book A has no author - it is edited by a group of people, and each chapter is written by individuals. You can't really say "whose" work it is. The rules developed over the past 150+ years say that a book in this situation has its "main entry" as title. It is arbitrary, but it works.

Example B - is written by a single person, so it has the author as its main entry.

Why does Example B have two alphanumeric sequences?

DS796 = Cities in China.

H7 is a pre-assigned number for Hong Kong. A book about Shanhgai would have a number of DS796.S2... These type of alphabet-number combinations are called "geographic subdivisions" or "Geographic Cutter".

Alphanumeric sequences are also often used to specify a narrow subject scope within a class number. For example, RA644 is for infectious diseases & different types of diseases are given pre-assigned Cutters.

RA644.C3 - Cholera
RA644.I6 - Influenza
RA644.M2 - Malaria
RA644.P9 - Polio

Cutter Numbers

How are these alphanumeric sequences made?

Charles Cutter (1837-1903) was a librarian in Massachusetts in the USA and his Rules for a Dictionary Catalog and his Expansive Classification laid the basis for how English language libraries are organized.

One of his inventions was the Cutter Table. It allows one to arrange names or titles in an alphanumeric sequence forever.

It's not hard to arrange things alphabetically with a finite set. But if you are constantly receiving new material, and don't want to keep changing the assigned numbers, you need something flexible.

Cutter Table from the US Library of Congress.

For fun, you can visit Kyle Banerjee's Cataloging Calculator, which can make Cutters for you.

Librarians follow the basic table and then check against what their library owns to make to make sure the numbers are not duplicate.

Why are some Cutters longer than others?

If a certain areas or disciplines are "crowded", one must cutter further to be able to inter-file correctly.

Example C

Classification number  Main entry  - Author's name or book title (if there is no author)
E184.C5 C45 1991  Chen, Huaidong
E184.C5 C466 2002  Chen, Shehong
E184.C5 C468 1995 Chen, Yanni. (Chen Yanni : Niuyue yi shi)
E184.C5 C4685 1997 Chen, Yanni. (Zao yu Meiguo, Chen Yanni cai fang.)
E184.C5 C473 1998 Chin, Frank


Example D

TK Electrical Engineering
5103.2 Telecommunications (TK5101-> TK6720)
.I54 Title of Journal (International journal of wireless information networks)

Why does this call number lack a publication year?

This is a periodical. It has no year of publication, because it has been published four times a year since 1994 and may continue to be published forever.

When you see a classification number in the Library Catalog that has no publication year, it is most likely a periodical.

LC Classification Outline

Basic Outline of LC Classification is listed below. The links will bring you to the detailed outline for each letter.

A - General works

B - Philosophy, Psychology, Religion

C - Auxiliary Sciences of History (e.g., numismatics or genealogy)

D- World History & the History of Europe, Asia, Africa, Australia, New Zealand, etc. (DS = Asia)

E and F - History of the Americas

G - Geography, Anthropology, Recreation

H - Social Sciences (including Economics)

J - Political Science

K - Law

L - Education

M - Music

N - Art & Architecture

P - Language & Literature

Q - Science & Math

R - Medicine

S - Agriculture

T - Technology & Engineering

U - Military Science

V - Naval Science

Z - Library Science, Publishing, Bibliography, Information Sources

How to Read a Call number

This video comes from  Larentian Library at Douglas College in New Westminster BC.  (1 min, 45 seconds)

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