Date: February 18 2022
Summary: An overview of the RDF and how it works
Keywords: #rdf #overview #triplet #graph #framework #archive
W3C, "RDF 1.1 Concepts and Abstract Syntax." https://www.w3.org/TR/rdf11-concepts/ (accessed Feb. 18, 2022).
The Resource Description Framework (RDF) is a family of specifications created by the World Wide Web Consortium (W3C) and formally adopted by W3C in 1999. Data mapped into the RDF form into triplets called RDF statements (also known as Semantic Triplets).
These triplets, or statements, are comprised of three components called the subject, the predicate, and the object. In summary, these components are described as:
Subject - this denotes a resource where anything can be a resource.
It is synonymous with the idea of an entity in other data models.
Predicate - traits or aspects of a defined resource and expresses the relationship between a Subject or a given Object.
Object - the target of the predicate and is similar to a resource in that anything can be an Object.
What the RDF statement compactly communicates is that there holds some relationship, indicated by the predicate, between the Subject and Object.
Example RDF statements are:
The sky is colored blue.
Grass is colored green.
The ocean is colored blue.
Taking the statement "The sky is colored blue." the Subject is the phrase "sky", the Predicate is the verb phrase "is colored", and the Object is the final phrase, "blue". Moving forward from this example, it may be useful to think of the RDF statement as a labeled directed multigraph where components of the statement are typically broken down and stored in Relational Database Management Systems or native RDF file storage formats. Here is a way of visualizing the triplet for the given statements above:
graph LR sky --is colored--> blue ocean --is colored--> blue grass --is colored--> green
The RDF triples "The sky is colored blue.", "Grass is colored green.", and "The ocean is colored blue" can all be represented as a Directed Multigraph \(G\). The nodes \(sky\), \(ocean\), and \(grass\) are Subjects, the nodes \(blue\) and \(green\) are Objects, and the edge \(is colored\) is the Predicate in these RDF triple.
Zelko, Jacob. Overview of the Resource Description Framework (RDF). https://jacobzelko.com/02182022165447-rdf-overview. February 18 2022.