EDUC 765
Trends and Issues in Instructional Design
The Library of Congress (LoC) classification system was developed in the late 19th and 20th centuries to organize the book collections of the LoC. The system was eventually adopted by large academic libraries, and it is now used around the world. (Source)
The LoC system divides all knowledge into 21 classes; each represented by a letter of the alphabet. Each class is then further divided into subclasses, and each subclass includes a loosely hierarchical arrangement of the topics it covers, going from general to the more specific. Relationships among the topics are similar to an outline. (Source)
Though the LoC system intends to “divide knowledge,” it does not have a theoretical basis. Instead, categories and subjects are divided in an enumerative manner for practical needs. In short, the classes and subclasses in the system are only meant to be used as a guide to the books in a collection, not the collective knowledge of the world.