Linked Data uses the web to connect related pieces of information. This information is published on the web in RDF datasets which use either OWL ontologies or RDFS vocabularies to define the types of the individual data elements and the relationships between them. Through the RDF linkage of related pieces of information in the different datasets Linked Data can be queried like a global database (using SPARQL) and traversed by following the (RDF) links connecting individual data elements. Linked Data (a.k.a. the Web of Data ) is an important goal of the Semantic Web.
The web of data is created using HTTP, URIs and RDF and the following design principles:
- Use URIs as names for things.
- Use HTTP URIs so that people can look up those names.
- When someone looks up a URI, provide useful information, using the standards (RDF, SPARQL).
- Include links to other URIs. so that they can discover more things.
Information published using the above design principles allows others to reuse this information and create innovative applications like those based on the linked data published by data.gov.uk.
The yearly snapshots of Linked Data uptake depicted in the Linking Open Data Cloud Diagrams highlight its increasing useage.
The State of the LOD Cloud provides information on the structure and content of the LOD Cloud including the extend to which LOD data sources implement recommended best practices for publishing Linked Data.
The power of Linked Data for is starting to be demonstrated. For example as discussed in the article Video Linking: Archives and Encyclopedias the ability to explore data by navigating from sets of things to other sets of things is becoming a reality.
The Presentations page contains a number of selected presentations that give an overview of different aspects of the Semantic Web and Linked Data.
Interlinking and Reuse
Identifying and reusing (the potentially multiple) published representations of the same real-world objects.
Tools facilitating reuse and the interlinking of datasets include:
- The LIMES link discovery framework and the COLANUT (Complex Linking in a NUTshell) interface that allows LIMES to discover and suggest class and properties matchings for linking.
Business Value of Linked Data
LOD SPARQL Endpoint
Linked Data Examples