Linked Open Vocabularies (LOV)

One of the main barriers to the deployment of linked data is the difficulty that data editors have to determine which vocabularies to use to describe their semantics. These vocabularies provide the "semantic glue" that allows simple data to become "meaningful data".

Linked Open Vocabularies (LOV) is a catalog of vocabularies available for reuse with the aim of describing data on the Web. LOV collects metadata and makes visible indicators such as the connection among different vocabularies, version history, maintenance policies, together with past and current references (both to individuals and organizations). The name of this initiative (Linked Open Vocabularies - LOV) has its root in the term Linked Open Data - LOD.

The main goal of LOV is helping the editors of linked data  and vocabularies to evaluate the resources (vocabularies, classes, properties and agents) already available and thus promote the highest possible reuse, appart from providing a way for the publishers to add their own creations.

LOV began in 2011 under the Datalift research project and hosted by Open Knowledge International (formerly known as Open Knowledge Foundation). Currently the initiative has the support of a small team of data curators / reviewers and programmers.

To facilitate the reuse of well-documented vocabularies (with metadata), several ways to access the data are provided:

• Through a user interface, with a browsing environment and searches (the web page itself).
• Through a SPARQL endpoint to make queries to the knowledge graph.
• Through a API REST.
• By means of a data dump, both from the knowledge base of LOV (in Notation3 format), as well as from the knowledge base plus the vocabularies themselves (in N-Quads) format).

Currently, the registry identifies and lists:

• 621 vocabularies (RDF vocabularies -RDFS / OWL- defined as schemas (T-Box) for the description of Linked Data)
• About 60,000 terms (between classes and properties).
• Nearly 700 agents (creators, contributors or publishers, and both people and organizations)

Among all the vocabularies, 34 has a term in Spanish, which allows a wide field of work for the Spanish community. 

LOV is a clear example of the importance of correctly documenting vocabularies with metadata. The value of metadata lies in its ability to classify and organize information in the most efficient way, providing greater intelligence and knowledge of superior quality, which facilitates and drives automation initiatives, review of compliance, collaboration, open data and much more .