If you grew up going to your grade school library or local public library you are probably familiar with the Dewey Decimal call number tags being on the items you borrow. Most college and university libraries use Library of Congress call numbers instead.
Both systems are systems of numbers and letters designed to organize items (books, movies, music, etc...) by topic or subject.
In the CMCC Learning Commons we us the Library of Congress system.
Video from the: Yavapai College Library
Items are shelved from left to right and top to bottom. When you get to the bottom of one bay (aka column of shelves) you go to the top of the next bay.
Each call number in the LC system refers to different subjects of interest, from Art to Zoology, below are links that explain what topics are under each letter range.