Pääluokittelussa

Pääluokittelu refers to the primary categorization system used to organize information in institutions such as libraries, archives, and information centres. It is the level of classification that places an item into one of several major divisions before it is further subdivided into more specific categories. In Finland, the most common main classification framework is the Systems of Library Classification (SLC), which aligns with international standards while allowing national adaptations. This system assigns a broad topic to each item, typically represented by a letter or a code, and thereby creates a hierarchical structure that simplifies both retrieval and administration.

The purpose of pääluokittelu is to provide a clear and logical grouping of materials so that patrons can efficiently locate resources. It also supports cataloguing consistency, as each main class has defined rules for assignment. The method of creating main classifications usually involves analysis of subject matter, relevance to user needs, and coherence with existing national or international standards. In practice, grades of main classification are often derived from subject specialists who examine subject terms and assign them to appropriate classes.

Pääluokittelu plays a key role in integrating digital and print holdings within a single collection. By establishing a uniform top-level structure, libraries can maintain order across diverse media, facilitate interlibrary loan processes, and support data harvesting for cataloguing. The system is continuously reviewed and updated to reflect changes in knowledge and user behaviour, ensuring that it remains effective in a rapidly evolving information landscape.