F.28 Schema.org 

F..28.1 Overview 

Schema.org is a collaborative, community activity with a mission to create, maintain, and promote schemas for structured data on the Internet, on web pages, in email messages, and beyond. 

From https://en.wikipedia.org/wiki/Schema.org

See also: https://schema.org/

F.28.2 Top-level 

Thing 

• Action 
• CreativeWork 
• Event 
• Intangible 
• MedicalEntity 
• Organization 
• Person 
• Place 
• Product 

F.28.3 Key characteristics 

A generic top-level data model with lightweight (or no) foundational ontological commitments. 

F.28.4 Relevant extracts 

Extracts from: https://schema.org/docs/datamodel.html

Extract 1 – Data Model Design 

The data model used is very generic and derived from RDF Schema (which in turn was derived from CycL, see History section for details ...). 

1. We have a set of types, arranged in a multiple inheritance hierarchy where each type may be a sub-class of multiple types. 
2. We have a set of properties: 
   1. each property may have one or more types as its domains. The property may be used for instances of any of these types. 
   2. each property may have one or more types as its ranges. The value(s) of the property should be instances of at least one of these types. 

The decision to allow multiple domains and ranges was purely pragmatic. While the computational properties of systems with a single domain and range are easier to understand, in practice, this forces the creation of a lot of artifical types, which are there purely to act as the domain/range of some properties. 

Like many other systems, the schema presented here can be extended (with a few types like Class and Property and a few properties like domainIncludes and rangeIncludes) to allow for reflection, i.e., for the schema to be represented in terms of itself. 

Extract 2 – Not intended to be a 'global ontology' 

The type hierarchy presented on this site is not intended to be a 'global ontology' of the world. When founded in 2011 it was strictly focussed around the types of entities for which the project's founders (Microsoft, Yahoo!, Google and Yandex), could reasonably expect to provide some special treatment for via search engines. As the project has evolved, introducing more community collaboration and extension mechanisms, its scope has expanded gradually. However it is still the case that schema.org is not intended as a universal ontology. We expect it to be used alongside other vocabulary that shares our basic datamodel and our use of underlying standards like JSON-LD, Microdata and RDFa.

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Continue to Appendix G: Prior ontological commitment literature