Knowledge Graph知识图谱—4. Linked Open Data & Semantic Web Programming

4. LOD & Semantic Web Programming

4.1 Linked Open Data

uses techniques like URIs, RDF, RDF schema for publishing knowledge on the Web
HTML has a concept for interlinking scattered information, known as hyperlink. LOD uses that principle, too.

Linked Open Data is RDF data that is provided in a distributed manner.
URIs are used as simple identifiers and linked to data in LOD.

4.1.1 Links in Linked Open Data

HTML Links vs. Links in Linked Open Data
Links in Linked Open Data are always explicitly typed. The semantics of the link is thus interpretable, given that the predicate is defined in a schema.
owl:sameAs* : Links two identical resources. This is required due to the non-unique naming assumption
rdfs:seeAlso: General link to other resources
foaf:homepage: Link to (HTML) homepage

4.1.2 Linking to a Schema

Luckily, everything is identified by a URI (also properties and classes), btw: this also works for “built in” schemas (rdf:type)

4.1.3 Four Principles of Linked