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OpenAnnotationIO

Principles

The OAIO Annotation Data Model is defined using the following basic principles:

  • An Annotation is a rooted, directed graph that represents a relationship between resources.
  • There are two primary types of resource that participate in this relationship, Bodies and Targets.
  • Annotations have 0 or more Bodies.
  • Annotations have 1 or more Targets.
  • The content of the Body resources is related to, and typically “about”, the content of the Target resources.
  • Annotations, Bodies and Targets may have their own properties and relationships, typically including creation and descriptive information.
  • The intent behind the creation of an Annotation or the inclusion of a particular Body or Target is an important property and represented by a Motivation resource.

The following principles describe additional distinctions regarding the exact nature of Target and Body:

  • The Target or Body resource may be more specific than the entity identified by the resource’s IRI alone. In particular,
  • The Target or Body resource may be a specific segment of the resource.
  • The Target or Body resource may be styled in a specific way.
  • The Target or Body resource may be a specific state of the resource.
  • The Target or Body resource may be included in the Annotation to play a specific role.
  • The Target or Body resource may be any combination of the above.
  • The resource with these constraints is a separate resource from the Annotation, Body or Target, and is called a SpecificResource.
  • The SpecificResource refers to the source resource and the constraints that make it more specific.
  • The identity of the SpecificResource is separate from the descriptions of the constraints.
  • The Body resource may be a choice between multiple resources.

The properties of external resources, such as Bodies and Targets, included in the Annotation document are intended as hints to the client, and are not to be considered authoritative information. This includes properties such as the created time, the creating agent, the modification time, any rights assertions, format, language or text direction of the external resource.