Each book in the library has a unique call number. A call number is like an address; it describes the exact location of the book and tells where to find the book on the shelves.
Call Numbers can appear:
On Book Spines
Vertically
or
Horizontally
In the Catalog
WB 100 H322p 1998
WB 100 H322p 1998
Note that the same call number can be written from top-to-bottom or from left-to-right.