Service description

The General Finnish Ontology YSO is a trilingual (Finnish, Swedish, English) ontology consisting mainly of general concepts, but which also contains a large number of concepts specific to various fields. YSO's Swedish language version is ALLFO.

Ontology refers to a hierarchy of concepts, which describes concepts and relations between them in some topic area in a machine understandable format and it identifies the concepts with identifiers (URI) instead of terms.

YSO has been drawn on the basis the content description needs and concepts within the Finnish cultural sphere and it is intended to be used for descriptions especially, when the topics of materials to be described are varied.

YSO is based on General Finnish Thesaurus (YSA) and General Finnish Thesaurus in Swedish (Allärs). Concepts in YSO and concepts in YSA and Allärs have been linked to each other with equivalence relationships.YSO has also been linked to Library of Congress Subject Headings (LCSH).

YSO contains over 30,000 concepts and it grows by approximately 1,000 conecpts every year.

YSO is included in the KOKO ontology.KOKO is a collection of Finnish core ontologies, which have been linked to each other. KOKO contains approximately 50,000 concepts.

Joining the service
  • No customer relation is required to use the service
  • Free of charge

YSO is free for all users through Finto service.

Standards used

ISO 25964-1:2011 (Information and documentation - Thesauri and interoperability with other vocabularies – Part 1: Thesauri for information retrieval)

ISO 25964-2:2013 (Information and documentation – Thesauri and interoperability with other vocabularies – Part 2: Interoperability with other vocabularies)



Contact information
Service address
Background information

Customer wiki has more info on YSO, including instructions how to suggest new concepts for YSO.

Service users
  • Enterprises
  • Organisations
  • Private individuals
Steering responsibility

National Library of Finland

Organisation model
  • Networking
  • Service is developed as part of basic operation of National Library
Index terms: