Resource Description Framework is a specification originally designed as a model for metadata. It is used as a general method for conceptual description or modeling of information that is implemented in web resources. It is the native way of describing linked data. RDF as a framework can be expressed in various data formats like XML. RDF data takes the form of ‘triples’ (each atomic piece of data has three parts, namely a subject, predicate and object), and can be stored in a specialised database called a triple store.

Source: Open Data Handbook. https://opendatahandbook.org/glossary/en/