Error situation during execution of an ABAP program. Exceptions are treatable (statements TRY, CATCH) or untreatable. Untreated exceptions result in a runtime error. An exception is triggered either by the ABAP runtime environment due to error situations that are not foreseeable by the static program check, or by the RAISE EXCEPTION statement. Before release 6.10, exceptions could be defined only in interfaces of function modules and methods. As of release 6.10, there are class-based exceptions, which include the catchable runtime errors.