Structure of a Call Number: The full letter and number combination assigned to a book is known as a Call Number. The call number is a code to tell where a book is located in the library and what it is about. The call number can be found on the sticker attached to the book’s spine. At the Milner Library, the call number will also appear in the online catalog along with the Floor # (https://library.illinoisstate.edu/).
The first two lines of the call number include the letters and numbers for the specific subject. The first section is always organized in alphabetical order. (P is before PR. PR is before PS). The second section is always in numerical order. (30 is before 300. 300 is before 303.)