(fhpd) help up up [num-levels] The up (down) command modifies the current frame location(s) by adding (subtracting) num-levels. Call stack movements are all relative, so up effectively "moves up" (or back) in the call stack, to a frame that has existed longer, while down "moves down" in the call stack, following the progress of program execution. I'm pretty sure that is backwards; Up goes to the top of stack; down goes to the bottom.