Acronym for Resource Description Framework.

A framework for the semantic description of resources on the web, in such a way that the representations on the web are given meaning so that the data can be processed automatically. RDF is not a format, but there are different forms of representation -XML, N3, Turtle, etc. [TSI-RPSI Application Guide]

It is an infrastructure to semantically describe resources, that is, to give meaning to what we represent so that the machines understand it. RDF can be represented in different formats: XML, N3, Turtle, etc. [CTIC Foundation]