Library of Congress Classification (LCC)
The POSTECH Library organizes its collection using the Library of Congress Classification (LCC) system.
As a science and technology-focused library, POSTECH adopts a more detailed classification scheme to better reflect subject-specific resources than general comprehensive universities.
Main Academic Classification Areas
A | General Works | K | Law | R | Medicine |
B | Philosophy | L | Education | S | Agriculture |
C-F | History | M | Music | T | Technology |
G | Geography | N | Fine Arts | U | Military Science |
H | Social Sciences | P | Language and Literature | V | Naval Science |
J | Political Science | Q | Science | Z | Library Science |
What is a Call Number?
A call number is a unique alphanumeric code printed on the spine of a book that indicates its exact location on the shelf.
- Alphabetic Class Code
- Represents the general subject area.
- Example: “Q” = Science, “QA” = Mathematics.
- Classification Number
- Further categorizes the subject into a specific topic.
- Example: “QA76” = Computer Science
- Author Code
- A combination of letters and numbers based on the author’s name or book title.
- Example: “QA76.F45” → “F45” = Feynman, Richard P.
- Publication Year
- Indicates the year the book was published.
- Example: “1996” means it was published in that year.
- Copy Number
- Used to distinguish individual copies when multiple copies of the same book exist.
- Example: “C4” indicates the fourth copy.
Shelving Order of Call Numbers
- Alphabetical Order
- Books are first arranged alphabetically by the initial letters of the call number.
- Example: QA → T → TA → TJ → Z
- Numerical Order
- If the initial letters are the same, items are ordered by the numeric part.
- Example: TJ5 → TJ171 → TJ173
- Decimal Order
- The Author Code is treated as a decimal and sorted accordingly.
- Example: TJ173 .C5 → TJ173 .C545 → TJ173 .C7
- Publication Year
- Indicates the year the book was published.
- Example) “1996” indicates the year of publication.
- Publication Year and Additional Elements
- Elements such as the publication year, volume number, and copy number appear after the Author Code and determine the final shelving order.
- Example: TJ175 .M123 1975 → TJ175 .M123 1978
Call Number Example

Book Title: Feynman lectures on computation
Author: Richard P. Feyman
Call Number: QA76 .F45 1996 C4
QA | QA76 | QA76 .F45 | QA76 .F45 1996 C4 | |
---|---|---|---|---|
explanation | Books are first arranged alphabetically based on the initial letters of the call number. | If two books share the same initial letters, the following numbers determine the order. | The second letter-number combination appears after a decimal point. Elements that follow are treated as decimal values and are arranged in Hangul alphabetical order first, then in Roman alphabetical order. | The final part of the call number may include the publication year, volume number, or copy number. |
Order on the Shelf | QA T TA TJ TK TX Z | TJ5 TJ171 TJ173 TJ173.67 TJ175 | TJ173 .김26 TJ173 .홍65 TJ173 .C171 TJ173 .C5 TJ173 .C545 TJ173 .C557 TJ173 .C7 TJ175 .D48 | TJ175 .H34 TJ175 .M123 1975 TJ175 .M123 1978 TK781.67 .M53 .L48 1996 |