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Help with Library Research

What is a call number?

A call number is a set of numbers and letters that are given to a library item according to what that item is about. They are usually located on the spine of a book, near the bottom. Call numbers are used to organize and locate items on the library shelves. 

Note: If the item in question is an ebook, it will NOT have a call number in Novanet.

Reading call numbers

Novanet Libraries arranges items on the shelves according the the Library of Congress (LC) classification system, which organizes materials by subject, so that books on similar topics can be found near each other on the shelves. This can be very helpful to know when doing research for an assignment! 

(If you'd like to know more about the Library of Congress classification system, please follow this link: About Call Number Arrangement)

Each and every item in the library is assigned a unique call number. A call number is like an address, telling you where an item is located. They are read from the top line down.

An example call number would be PS 261 .P68 2006





First line: PS – LC Call numbers typically begin with one or two letters. These letters tell you the general topic the book falls under (For example, the B section contains books on philosophy)

Second Line: 261 – Read the first number as a whole number (1, 34, 100, 258…)

Third Line: .P68 – The third part may be a combination of numbers and letters, or just letters, usually following a decimal. Read letters alphabetically, and numbers as a decimal.

Fourth Line: 2006 – The year the book was published. Not every call number includes the publish year, but it can help differentiate between editions or republications.

Finding the item on the shelf

Call numbers look complicated, but all you need to remember is that it’s telling you where to go to find the item you’re looking for.

In the above example, you’d start by looking for the ‘PS’ shelves, which will come after PR and before PT. Most libraries, including the Mount, will have cards or labels on the ends of each aisle to tell you what range of letters that aisle contains.

Once you’ve found the PS shelves, you read the second part of the call number, 261. 261 comes after 260, and before 262.

The 3rd part, the decimal number, can be the trickiest. 261.P68 would come before PS 261 .Y34, but after PS 261.P5

Not every book will have its published year on its call number, but they will be shelved chronologically (so 2000 before 2010, for example).

And remember, if you are uncertain how to find an item or you would like help understanding call numbers, the staff at the Mount Library are more than happy to help you find what you are looking for!