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Finding Books on the Shelf: How do I use it?

Most academic libraries use the Library of Congress Classification System to organize their materials. This guide will show you how to use that system to find materials in the library.

Where will you find call numbers?

When you find books in the online catalog that look useful, always remember to write down the call number or take a picture of it with your mobile phone!  A call number is printed on the spine of a book and that is what you will use to locate a specific book among the hundreds of other books on the shelf.

Upclose photo of the label on the spine of 5 books upright on the shelf.

A Sea of Choices

Image long row of library shelves filled with books.

Order of Call Numbers on a Shelf

Here is a list of call numbers, with explanations of how they were put in order:

  1. LA2301 .M37
  2. LB2327 .M3 (LB comes after LA)
  3. LB2328 .B37 (2328 comes after 2327)
  4. LB2328 .C34 (C comes after B)
  5. LB2395 .B35 2009 (2395 comes after 2328)
  6. LB2395 .B87 2003 (Both start with LB2395 .B, decimal .87 comes after .35)
  7. LB2395 .C45 2007 (C comes after B)
  8. LB2395 .D739 2010 (D comes after C)

Here is how they would look on the shelf. You will notice that the LB2395 books all deal with similar subject content.

Image of six upright books with the spine showing. Four of the books have call numbers with arrows pointing to them with the title of that book out to the side. Book 1: "Guide to Learning and Study Skills" -- LB 2395 .D739 2010. Book 12: "Student's Guide to Presentations" -- LB 2395 .C45 2007. Book 3: "Essential Study Skills" -- LB 2395 .B87 2003. Book 4: "Studying Arts and Humanities" -- LB 2395 .B35 2009.

Reading Call Numbers Line by Line

Call numbers are read in pieces:

PN --  The first two letters are in alphabetical order: A, B, BF, C, D...P, PN, PQ, Q, QS...

1993.45 -- The second line is a whole number: 1, 2, 45, 100, 1000, 1993, 1993.45, 1993.48 ...

A75 -- The third line is a combination where you read the letter alphabetically first then the number as a decimal: A6, A67, A7, A75, B1, B26 ... (see Cutter Number)

1980 -- The last number is the year of publication.