This video explains how to use Library of Congress (or LC) call numbers to locate items in the library.

Video Transcript:

This video explains how to use Library of Congress (or LC) call numbers to locate items in the library.

The Library of Congress Classification System uses a combination of letters and numbers to arrange materials on library shelves by subject. These call numbers provide an address for each item on the shelf.

When you look up an item in the library’s catalog, the location, call number, and status will help you determine if the item is available and where to find it in the library.

The call number listed in the catalog will correspond to the label on the spine of the item.

On the label, call numbers are read in alpha-numeric order line by line from top to bottom.

The first line is read in alphabetical order. In this example, we see call numbers that start with the letters Q, QA, and QE so we list those alphabetically beside one another.

The second line is read as a whole number. In this example, we see that all of the call numbers start with the letters QE so we would focus on the second line to determine the order using the numbers 86, 862, 2860, and 2862.

For the third line, read the letter alphabetically and the number as a decimal. Here, we see that S comes before T and the number .3 comes after .2 but before .35. If there is a fourth line, you would read it the same way.

The last line is usually the year that the item was published and it is read in chronological order.

Once you have the call number of an item, use the signs at the end of the shelves to guide you to the proper location.

As you walk down the row, remember that the moveable shelves may not always align as you cross the aisle, so keep paying attention to the signs at the ends of each row.

When you find the appropriate aisle, call numbers run left to right, top to bottom on each shelf.

The Library of Congress Classification System groups similar topics together so once you locate one book using its call number, you can browse the books nearby on the shelf to find related materials.

If you need help using call numbers to locate materials within the library, feel free to ask a librarian.