Thinking on the Web: Berners-Lee, Gödel and Turing

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RESOURCE DESCRIPTION FRAMEWORK (RDF)

OVERVIEW

The eXtensible Markup Language (XML) is a universal meta-language for defining markup.² It provides a uniform framework for exchanging data between applications. It builds upon the original and most basic layer of the Web, HyperText Markup Language (HTML). However, XML does not provide a mechanism to deal with the semantics (the meaning) of data.

Resource Description Framework (RDF) was developed by the W3C for Web-based metadata in order to build and extend XML.³ RDF’s goal is to make work easier for autonomous agents and automated services by supplying a rudimentary semantic capability.

RDF is a format for data that uses a simple relational model that allows structured and semistructured data to be mixed, exported, and shared across different applications.⁴ It is a data model for objects and relationships between them and is constructed with an object–attribute–value triple called a statement. While XML provides interoperability within one application (e.g., producing and exchanging bank statements) using a given schema, RDF provides interoperability across applications (such as importing bank statements into a tax calculating program).

In this chapter we highlight some basic characteristics of Hypertext Markup Language (HTML) and eXtensible Markup Language (XML). Then we introduce Resource Description Framework (RDF) and present fundamental concepts such as resources, properties, and statements. We define the subject, predicate, ...