Open Annotation Guiding Principles

1. The effort focuses on interoperability for annotations. Its goal is to allow the sharing of annotations across clients, servers, and applications. It will not, in any way, prescribe user interfaces, internal architectures or internal data structures.
2. The interoperability framework focuses on maximizing the benefit of annotations with unrestricted access, hence Open Annotations. However, it does not preclude restricting access to annotations or their constituent resources. It does not define any authentication or authorization mechanisms, but does not preclude the use of existing or new techniques.
3. The interoperability framework promotes the use of existing publish/subscribe techniques for discovering annotations. It does not specify a client-server protocol, yet does not preclude further specifications from introducing a protocol that builds upon the framework.
4. The interoperability framework is expressed in terms of the Architecture of the World Wide Web, and the best practices from the Linked Data effort.
5. The interoperability framework regards an Annotation as a serialization of a Graph. Best practices are recommended for serialization formats of RDF Graphs.
6. Typically, an Annotation expresses a relationship between one Body, and one or more Targets, where the Body is somehow “about” the Target(s). However, certain types of Annotations may lack an explicitly specified Body, such as bookmarks or highlights.
7. The Annotation, Body and Targets are individual resources, identified with URIs, which may have distinct metadata including especially provenance information such as authorship and date of creation or modification.
8. The representations obtained by dereferencing the Body or Target URIs may be of any media type. A Body may be a video about a Target which is an image.
9. The Body or any Target may be part of a resource, such as an Annotation where the Target is a section of an image or a time range in audio media. The interoperability framework includes solutions for handling resource segments, leveraging existing mechanisms where possible.
10. The correct interpretation of an Annotation may be conditional on additional information beyond the URIs of the Body and Target(s). Many Annotations have Body or Target resources that change over time, or have different representations available via content negotiation, and only a particular representation is intended by the Annotation. The interoperability framework includes solutions for describing this additional information, leveraging existing mechanisms where possible.