What are semantic technologies?
The term "semantic technologies" describes tools used to organise, categorise and link data according to their meaning (semantics). Some semantic tools such as taxonomies or catalogues have been in use for centuries. Think of a library catalogue - a paper card system used by readers and librarians to find information in large organised collection. Others tools such as semantic web or knowledge inference engines are more recent and are under active development.
| Purpose | Technology | How it works | Examples |
| Concept organisation and naming | Ontologies, taxonomies, thesauri (controlled dictionaries) | Agreeing on using terms and what they mean. | QUDT, PhySH, units of measure ontology |
| Data storage and retrieval | Triple stores, resource description frameworks, SPARQL | Providing a format in which organised data are stored and mechanism (query language) to interact with them. | GraphDB, Neo4J, GraphQL |
| Enable data interoperability and linkage | Knowledge graphs, linked data such as JSON-LD | Combining several technologies together to either enable or enhance semantic capabilities. For example, knowledge graphs can be combined with relational databases. | DCC schema, JSON-LD, linked data EU tutorial |
| Knowledge inference | Semantic reasoners, description logic, inference rules, semantic web | Using logical and mathematical rules to infer knowledge from semantically annotated data. | MathQL, semantic web tutorial |