Local files

See also local files:

W3C and related



Security and cryptography


Verifiable Credentials

Multiple roots (which leads to graphs)

Graph note keeping

Linked Data

Linked Data format

Linked Data is a method of publishing RDF data on the Web and of interlinking data between different data sources. Linked Data can be accessed using Semantic Web browsers. However, instead of blindly following nondescript links between HTML pages, Semantic Web browsers enable users to navigate by following self-described RDF links. It also allows the robots of Semantic Web search engines to follow these links to crawl the Semantic Web.

Linked Data cloud

Linked Data browsers

JSON-LD format

JSON-LD is a JSON-based format to serialize Linked Data. JSON-LD is primarily intended to be a way to use Linked Data in Web-based programming environments, to build interoperable Web services, and to store Linked Data in JSON-based storage engines.


Solid - Tim Berners-Lee and Lalane Kagal

Solid (derived from "social linked data") is a proposed set of conventions and tools for building decentralized social applications based on Linked Data principles. It relies as much as possible on existing W3C standards and protocols. These are:
Solid project and specifications
Solid and W3C
Inrupt company
Other software




Legal entities



EC ISA, PO, SEMIC and related


Publications Office (PO)

EC Webgate




Started by Mark Musen 1987, much work done by Natasha Noy.

Graph databases



Architecture and blockchain

Architecture - REST - Web Services

Blockchain and Ontology

Semantics - initiatives


See also local files.

Application development

Application development



Wikipedia, media, ...


Applications - general

Applications - vendors

Applications - music

Applications - trust

Semantics - RDF - Turtle - SPARQL - OWL - SKOS - DC

Interesting: cryptographic definition of semantic security: QUOTE In cryptography, a semantically secure cryptosystem is one where only negligible information about the plaintext can be feasibly extracted from the ciphertext. Specifically, any probabilistic, polynomial-time algorithm (PPTA) that is given the ciphertext of a certain message m (taken from any distribution of messages), and the message's length, cannot determine any partial information on the message with probability non-negligibly higher than all other PPTA's that only have access to the message length (and not the ciphertext). This concept is the computational complexity analogue to Shannon's concept of perfect secrecy. Perfect secrecy means that the ciphertext reveals no information at all about the plaintext, whereas semantic security implies that any information revealed cannot be feasibly extracted.

Semantic Web - basics

Semantics - Turtle and RDF

Semantics - SKOS - 2009 - W3C

The Simple Knowledge Organization System (SKOS) is an RDF vocabulary for representing semi-formal knowledge organization systems (KOSs), such as thesauri, taxonomies, classification schemes and subject heading lists. SKOS is based on RDF. In SKOS, conceptual resources (concepts) can be identified with URIs, semantically related through hierarchies and association networks, labeled with lexical strings, documented with notes, and aggregated into concept schemes.

SKOS can be used on its own, or in combination with more-formal languages such as OWL. SKOS can be seen as a bridging technology, providing the missing link between the rigorous logical formalism of OWL and the informal and weakly-structured world of Web-based collaboration tools, as exemplified by social tagging applications.

The aim of SKOS is not to replace original conceptual vocabularies in their initial context of use, but to allow them to be ported to a shared space, based on a simplified model, enabling wider re-use and better interoperability.

Semantics - DAML - superceded by OWL

Semantics - SPARQL - SPIN - SHACL

SPARQL - a recursive acronym for SPARQL Protocol and RDF Query Language. SPIN - SPARQL Inferencing Notation SHACL - Shapes Constraint Language

Semantics - W3C OWL

Semantics - SHACL

Ontologies and Vocabularies


Ontologies and Vocabularies - W3C - general

Ontologies and Vocabularies - W3C - CA and Provenance

Ontologies and Vocabularies - well-known

Dublin Core


OMG and related





Indices content available with semantic metadata

Ontology design patterns

Logic, Rules and Reasoners