Western Libraries

Introduction to Call Numbers

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Script of Video:

Have you ever seen a combination of numbers and letters on the side of library items and wondered what they were?

These are call numbers and they tell you where to find an item. The first section refers to the subject area of the item.

Read the first part in alphabetical order and the second part as a whole number.

The next section is a combination of a letter and a number which refers to the item's author.

Read the letter alphabetically and read the number as a decimal.

The final section refers to the year of publication. This is important to note since newer editions of the same item will have the same call number except the publications year will be updated. These are organized in chronological order.

There might be a volume number at the end too if the item is part of the series or multivolume set.

Items are put on the shelf in the library according to call numbers so items with similar subjects will be close to each other.

Use the library catalogue [We have a new Western Libraries website. You can search from the catalogu button on the main navigation bar.] to determine in which library the item is located. If you click on the location you get more information about where to find the item. For example, DBW stack use the book is in the stacks in the D.B. Weldon Library.

TAY stack is in the stacks at the Taylor library.

You can also see if the item is available or if it has been taken out and when it is due back in the library.

The catalogue might also include information about how long the item can be borrowed for.

If it is a NO LOAN item you can only use the book within the library.

If you see 2HR, this item is on reserve for 2 hours. Go to the Service Desk to find this one.

As well you can have the item's call number texted to your phone so you don't forget.

For example, in Taylor you'll have to find the correct floor location based on the type of material and the call number. Use the call number ranges at the top of each shelf to find which shelf your item is on. Then follow the call number sequence to get your book.

There is so much to know about finding library books from the catalogue so make sure you have it all handy when you come to the library. You can always ask the staff at the Service Desk for more help if you need it.


See also the Library of Congress and the Library of Arizona websites. Both have excellent visual descriptions of how to read a call number.