Comparison Between Dewey Decimal Classification (DDC) and Library of Congress Classification (LCC)

 

Comparison Between Dewey Decimal Classification (DDC) and Library of Congress Classification (LCC)

The Dewey Decimal Classification (DDC) and the Library of Congress Classification (LCC) are two prominent systems used to organize library materials by subject, facilitating easy location and retrieval of resources on shelves. DDC was developed by Melvil Dewey in 1876 and is widely used in public, school, and small academic libraries, while LCC was created by the Library of Congress in the late 19th century and is preferred in large academic and research libraries. Both systems are hierarchical and topic-based, but they differ in structure, scope, and application. 

Structure and Main Features

• DDC:
• Numeric system with 10 main classes ranging from 000 to 900.
• Each main class is divided into 10 divisions, and each division into 10 sections, using decimals for further subdivisions.
• Notation includes a three-digit number for the subject, followed by a cutter number for the author or title.
• Designed for flexibility in small to medium collections; can be expanded or abbreviated.
• Total of 99 second-level classes (two-digit subdivisions).
• LCC:
• Alpha-numeric system with 21 main classes denoted by letters (A–Z, skipping I, O, W, X, Y for future expansion).
• Each class has subclasses (additional letters), followed by numeric codes for topics, cutter numbers for authors, and often a publication year.
• More granular, with thousands of subclasses, suited for very large or specialized collections (e.g., over 500,000 items).
• Developed specifically for the Library of Congress’s vast holdings, allowing for precise categorization. 

Similarities

• Both classify materials by subject to group related items together.
• Hierarchical organization allows for broadening or narrowing searches.
• Used globally for shelving and cataloging, with call numbers printed on book spines.
• Aim to make library navigation intuitive for users. 

Differences

• Scope and Usage: DDC is simpler and more universal, ideal for general audiences in public libraries, but may lack depth for extensive collections. LCC is more detailed and customizable, better for academic environments with specialized topics, but can be complex to learn. 
• Notation: DDC uses purely numbers and decimals (e.g., expandable like 123.456), while LCC combines letters and numbers (e.g., less intuitive but more capacity for subclasses).
• Number of Classes: DDC has 10 main classes; LCC has 21.
• Advantages of DDC: Easy to understand, consistent across libraries, good for broad categories.
• Disadvantages of DDC: Can become cumbersome with long decimal strings in large libraries; some biases in original design (e.g., Western-centric).
• Advantages of LCC: Highly specific, scalable for growth, no length limits on notations.
• Disadvantages of LCC: Steeper learning curve, not as standardized outside academic settings. 

Examples of Classification

Here are some specific examples showing how the same or similar subjects are classified in each system, based on standard mappings: 

• General Works/Computer Science:
• DDC: 000 (Computer science, information, general works).
• LCC: A (General works), QA (Mathematics/Computer science).
• Example Book: “Introduction to Algorithms” might be DDC 005.1 (Data structures), LCC QA76.9.A43 (Algorithms).
• Philosophy and Psychology:
• DDC: 100 (Philosophy & psychology).
• LCC: B (Philosophy, Psychology, Religion).
• Example Book: “The Republic” by Plato – DDC 184 (Platonic philosophy), LCC B358 (Plato’s works).
• Religion:
• DDC: 200 (Religion).
• LCC: BL (Religions, Mythology).
• Example Book: “The Bible” – DDC 220 (Bible), LCC BS (Bible).
• Social Sciences:
• DDC: 300 (Social sciences).
• LCC: H (Social sciences).
• Example Book: “The Wealth of Nations” by Adam Smith – DDC 330.153 (Economics), LCC HB161 (Economic theory).
• Language:
• DDC: 400 (Language).
• LCC: P (Philology, Linguistics).
• Example Book: “English Grammar” – DDC 425 (English grammar), LCC PE1112 (English language grammar).
• Science:
• DDC: 500 (Pure sciences).
• LCC: Q (Science).
• Example Book: “A Brief History of Time” by Stephen Hawking – DDC 523.1 (Cosmology), LCC QB981 (Cosmology).
• Technology:
• DDC: 600 (Technology).
• LCC: T (Technology).
• Example Book: “The Art of Electronics” – DDC 621.381 (Electronics), LCC TK7815 (Electronics).
• Arts:
• DDC: 700 (Arts & recreation).
• LCC: N (Fine arts).
• Example Book: “History of Art” – DDC 709 (Art history), LCC N5300 (Art history).
• Literature:
• DDC: 800 (Literature).
• LCC: PN (Literature general).
• Example Book: “To Kill a Mockingbird” by Harper Lee – DDC 813.54 (American fiction), LCC PS3562.E353 (Lee’s works).
• History and Geography:
• DDC: 900 (History & geography).
• LCC: D (History general and Old World).
• Example Book: “Guns, Germs, and Steel” by Jared Diamond – DDC 303.4 (Social processes), LCC CB (History of civilization).