Final answer:
When casting in SPARQL and RDF, a range of XML Schema Definition (XSD) datatypes like xsd:string and xsd:int can be used, and custom datatypes may also be incorporated if properly defined.
Step-by-step explanation:
When CASTING SPARQL AND RDF, datatypes other than RDF specific datatypes can be used. SPARQL allows for casting to various datatypes defined in the XML Schema Definition (XSD). These datatypes include common ones like xsd:string, xsd:boolean, xsd:int, xsd:float, xsd:dateTime, among others. In addition to the standard XSD datatypes, SPARQL also permits the use of custom datatypes if they are appropriately defined in an RDF schema. However, care must be taken to ensure these datatypes are correctly handled by the query processor.