RDF's syntax is based on several standards and nonstandards.
The core standard at work is, of course, RDF. This W3C standard consists of two main parts and has evolved in two stages.
The first stage of standardization consisted of draft standards developed in 1999 and 2000. There are two main documents:
http://www.w3.org/TR/1999/REC-rdf-syntax-19990222. This document is the “RDF 1.0 Model and Syntax Final Recommendation.” Model just means underlying conceptual design.
http://www.w3.org/TR/2000/CR-rdf-schema-20000327. This document was not finalized for several years. It provides complex schema operations on RDF tags and is different from XML Schema.
The second stage of RDF standardization consisted of expanding and completing ...