Like the title says, it defines an XML format to write down the SPARQL (SPARQL Protocol and Query Language, pronounced sparkle) variable binding query results, trying to make it easy to handle in XML technologies especially XSLT (XPath) and XQuery. Only time will tell how well it succeeds.
The RDF graph query results from SPARQL queries already have a recommended format to use - RDF/XML, which I edited. There are also non-standard ones such as Turtle, which I wrote and named. I'm sensing a theme here :) Stop me now or I'll write another RDF syntax! Oops, I forgot
RXR which I've subsequently been told is pronounced just like R0XX0R.