How Libraries Classify Books (and How to Take Advantage of it!)

Most new items coming into the Duke libraries are now classified according to the Library of Congress ("LC" ) system.  (We used to use Dewey Decimal, but are phasing it out.)  LC assigns call numbers, which we use to shelve the books, by subjects. We use LC Subject Headings in our online catalog. Learning to use them can help you save time and find books you might not get using only keyword searches.

Use the LC system to browse for books

• Find a book that's relevant to your project by searching the online catalog using keywords.
• OR look at the list of major subject classifications and find your topic.
• Go to the stacks for the call number and see what other books we have on the topic. 

Use LC Subject Headings to search the catalog 

Know the LC Subject Heading you want?  Do a "Subject begins with" search in the online catalog.

Find LC Subject Headings in print using books available at the Perkins Reference Desk.

Search the online catalog for 'Subject Keywords'

• Example: Subject Keyword "yellowstone"
• Results: 407 hits. 
• Choose one or more of the results and click the title to see the full catalog record.
• Scroll down to see the list of Subjects.  These are LC Subject Headings.

• Click on one of them (Example: Yellowstone National Park - History).
• Choose 'Display matching record(s)' to see all items Duke owns with that Subject Heading attached.
• Choose 'Browse an alphabetical list' to see that Subject Heading and others that are related to it.