.CONTINUE : Continues execution of a stopped program.

.SKIP: Skip over the next statement or statements.

.STEP: Executes one or more statements.

.STEPOVER: Executes one or more statements but do not step into routines.

.TRACE: Continue execution, display each line of code as it is executed.

BREAKPOINT: Set and clear breakpoints for debugging.

CODE_COVERAGE: Return line numbers of executed and un-executed code within a routine.

PROFILER: Analyze the performance of IDL code.

SHMDEBUG: Print debugging information for shared memory segments.

STOP: Halt the execution of a running program or batch file.