Open knowledge format link data tpes

 Open Knowledge (and Open Data) standards do not prescribe a single, rigid "typed link" syntax. Instead, typed links in open knowledge systems are implemented using Linked Data principles, specifically RDF (Resource Description Framework) triplets and established Web Ontologies.

Core Structure: RDF Triplets

In an open knowledge format, connections between data points are expressed as typed relationships using a Subject-Predicate-Object model:

• Subject: The resource being described (e.g., Entity_A)
• Predicate (Typed Link): The specific, defined relationship type (e.g., schema:knows or dcterms:creator)
• Object: The target resource or literal value (e.g., Entity_B)

How Links Are Formally Typed

Rather than using generic hypertext links (<a href="...">), open knowledge frameworks map typed links to standardized Uniform Resource Identifiers (URIs).

Mechanism	Description	Example
Schema.org	Standard vocabulary for web-based structured data	[http://schema.org/contributor](http://schema.org/contributor)
Dublin Core (DCTERMS)	Common metadata standards for resources	[http://purl.org/dc/terms/references](http://purl.org/dc/terms/references)
FOAF (Friend of a Friend)	Links connecting people, organizations, and groups	[http://xmlns.com/foaf/0.1/knows](http://xmlns.com/foaf/0.1/knows)
OWL / RDFS	Formal ontology definitions expressing subclass and equivalency links	owl:sameAs, rdfs:subClassOf

Common Serializations

Open knowledge formats express these typed links using several common file types:

• JSON-LD: Embeds structured, typed links inside standard JSON objects.
• Turtle / N-Triples: Human-readable text formats designed specifically for RDF graphs.
• Wikidata Statements: Open graph property links (e.g., P31 for "instance of", P279 for "subclass of").