Which system classifies by subject and is commonly used for shelving and cataloging in libraries?

• A. Dewey Decimal System
• B. Interlibrary Loan (ILL)
• C. CREW Weeding Method
• D. Selection Criteria

Answer: (A)

Organizing library materials by subject is essential for quick locating and grouping related items. The Dewey Decimal System classifies information by subject and places items on shelves according to these subjects, using a hierarchical numeric scheme. It has ten broad classes (000–999) with subdivisions, so books on similar topics stay near each other and are easy to browse and shelve correctly. It’s widely used in many libraries, especially public libraries and schools (though some large libraries use other systems as well).

Interlibrary Loan is a service for borrowing materials from other libraries, not a method of classification. The CREW Weeding Method guides when to remove items from the collection, not how to organize them. Selection Criteria refers to the standards used to decide what to acquire, not how materials are shelved.