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What is a call number?: Home

How call numbers work

All books in the library are assigned a call number, usually found on the book spine. The call number represents what the book is about and acts like the book's address on the library's shelves or stacks. Because books on the shelves are arranged in call number order, you will find books on similar subjects shelved near each other.

At the Taft College Library, we use the Library of Congress (LC) classification system. LC call numbers are made up of letters and numbers and look something like this:

HB 3654 .A3 F66 2016

Read the call number from left to right. The first part of a call number, HB 3654, consists of a combination of one or two letters and a number that indicates a specific subject area.

The next part, .A3 F66, identifies a specific title within the range of books on that topic, 2016 is the date of publication.

call numbers

Finding your book once you have a call number

Once you have a call number for your book (or other item), you can locate it within the library, paying attention to the particular shelving area in the library. NOTE that the areas in the library are: Circulating Stacks, Reference Stacks, Oversized Stacks, and the DVD stacks.

Steps for finding your call number on the shelf

  1. Start with finding the first letter of your call number. For the example above, call numbers starting with HB are on the first tall row of books.
  2. Call numbers beginning with a single letter come before call numbers with a second letter, e.g.: H before HA, then HB, HV, and so on until HX.
  3. Once you are in the correct letter area (in this example, HB), the books are in number order, e.g.: HB 3717 comes after HB 3654 and before HB 3722.
  4. The next part of the call number is read like decimals, e.g.: HB 3717 .I929 R42 comes before HB 3717 .S73 1996
  5. Many books also include the year of publication. In this example it is 1996. This will help you find the right edition, if there is more than one.

Using call numbers to browse the shelves

Once you find a book on your topic, take the time to browse the books around the one you chose. You will find other books that may be related to your topic that you missed in your catalog search.