What Is A Call Number?

Like most academic libraries, JFKU organizes its books by subject according to the Library of Congress Classification System.

Each book in the library has a unique call number. You can think of the call number like an address; it tells you where the book is located in the library.

The example below illustrates how the call number sequence works:

Letters = broad subject areas:	BF	Psychology
Number = subdivision of above:	721	Child Psychology
alphanumeric = the author:	.P45	Piaget

There will be many books with the first two lines. However, the third line makes the whole call number unique to one particular book and usually indicates authorship. Some call numbers have more than one alphanumeric line.

How To Read Call Numbers

Call numbers are read line by line. There are two main types of call number types within the Library of Congress schema:

Scheme 1 involves only one letter-digit pair:

RJ	Read the first line alphabetically (R before RJ, RJ before S)
131	The second line is read as an integer (130 before 131; 131.55 before 131.6, etc.).
.L38	Read the letter alphabetically and the number as a decimal (.K38, .L293, .L38, .L4).
1991	This line is the year the book was published. Read it chronologically

There will be many books with the first two lines. However, the third line makes the call number unique to one particular book and usually indicates authorship.

Scheme 2 involves two alphanumeric lines:

RJ	Read the first line alphabetically (R before RJ, RJ before S)
131	The second line is read as an integer (130 before 131; 131.55 before 131.6, etc.).
.L38	Read the letter alphabetically and the number as a decimal (.K38, .L293, .L38, .L4).
K36	Read the letter alphabetically and the number as a decimal as above.
1991	This line is the year the book was published. Read it chronologically.

There may be many books with the first three lines. However, the fourth line makes the call number unique to one particular book and usually indicates authorship.

There are several call number formats used in the JFKU Libraries which deviate from the Library of Congress. These indicate theses, final projects, audio and video cassettes (all of which must be requested at the circulation desk).