RDF blank node
- 2025-04-05
In RDF, it is sometimes handy to be able to talk about resources without bothering to use a global identifier. For example, we might want to state that the Mona Lisa painting has in its background an unidentified tree which we know to be a cypress tree. A resource without a global identifier, such as the painting’s cypress tree, can be represented in RDF by a blank node. Blank nodes are like simple variables in algebra; they represent some thing without saying what their value is.1
Blank nodes can appear in the subject and object position of a triple. They can be used to denote resources without explicitly naming them with an IRI.1