Here's a sample call number, with explanation for each line:

QE -   indicates the general subject area; presented on the shelf in alphabetical order

862 -  number line which indicates more specifically the subject area; presented on the shelf in numerical order within the QE section

.D5 -  combination of letters and numbers that often represent the author's last name; presented on the shelf in alphabetical then decimal order

2006 - year of publication; presented chronologically on the shelf

Thanks to UCR and UMICH for these ideas.

Here's a sample call number, with explanation for each line:

370 - indicates general subject area (this number is read as a whole number); look for the section that begins with 370

.13 - indicates more specifically the subject area (this number is read as a decimal)

S61bu - represents the author's last name (should be read alphabetically) and the title of the item