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WorldCat Entity

Discover the general guidelines and standards for WorldCat Entity Data.

WorldCat Entity

A WorldCat Entity represents a specific instance of a thing. For example, a singular person, place, or work.

Each WorldCat Entity will contain a common set of descriptors:

  • Label. A label will appear at the top of the page. This label will be displayed in the preferred language, which can be changed at the bottom of the screen. For more information, see Set language.
  • Entity ID. An Entity ID is the unique identifier for the WorldCat Entity.
  • Entity Type. An Entity Type is the class of Entity that the WorldCat Entity is describing. For example, a WorldCat Person Entity would have an Entity Type of Person.
  • Reference. Each claim within the WorldCat Entity can have one or more references that identify the source or provenance of the claim.

Class

A class identifies the type of WorldCat Entity. Work, Person, Place, and Event are examples of WorldCat Classes. Classes are arranged in a hierarchical structure, with subclasses representing more strictly defined subsets of their hierarchically superior class. For example, Person is a subclass of Agent, therefore we can infer that all Person entities are a type of Agent, but not all Agents are Persons.

In this documentation, each class is described by a common set of terms:

  • Label. The preferred term for the class as defined by the ontology model.
  • URI. A unique resource identifier for the class.
  • Description. A brief natural-language explanation describing the basic characteristics of the class.
  • Subclass of. This identifies the hierarchically superior class of which the class is a more strictly defined subset.

Property

A property defines the relationship between two entities, or between an entity and a text string. Properties are assigned to their appropriate class within the class hierarchy and are inherited by all subclasses below it. 

In this documentation, each property is described by a common set of terms:

  • Label. The preferred term for the property as defined by the ontology model.
  • URI. A unique resource identifier for the property.
  • Description. A brief natural-language explanation describing the basic characteristics of the property.
  • Expected object. The class of entity to which the property may relate. The expected object may also be literal for text-based objects.

Diversity, Equity and Inclusion

OCLC recognizes the profound importance of Diversity, Equity, and Inclusion (DEI) in all that we do. Significant thought has been given to the crafting of WorldCat ontology labels and descriptions that are aligned with DEI values. We acknowledge that biases may be present in the current model, and we are actively engaging with the library community to understand and address these issues. The WorldCat ontology is not intended to be a static data model, and we will continuously strive to improve its clarity, inclusiveness, and descriptive breadth.

Please contact askqc@oclc.org with any questions or feedback regarding the WorldCat ontology.

Acknowledgement

OCLC acknowledges the efforts of all the people who participated in producing this documentation:

Amanda Brennan, Anne Washington, Becky Dean, Charlene Morrison, Laura Ramsey, Morgan Peters, Michael Phillips, Robin Six, Shanna Griffith