Books are arranged on the shelves by call number. Most call numbers used in the Temple University Libraries use the Library of Congress (LC) system, which alternates numbers and letters.
Items are shelved alpha-numerically. Call letters are placed in alphabetical order, with single letters preceding double letters:
Within a given alphabetical group, items are arranged in numerical order (whole numbers):
Items within the same group are further sub-divided alpha-numerically. Note how the numbers are read as decimals, arranged by value rather than length of number:
With this information in hand, you can go to the appropriate library and locate the book by call number.
For help checking out a book, see this FAQ, How do I check out a book?