但，本质上都是： However,the outward appearance is of peripheral importance when compared to the bits and their internal arrangement.It is the bits that"sense"the external stimuli arriving from the outside world via buttons,levers,keys on a keyboard,electronic communication lines,and even microphones and cameras.It is the bits that"decide" how to react to these stimuli and respond accordingly by directing other stimuli to the outside via displays,screens,printers,loudspeakers,beepers,levers,and cranks.但，本质上都是：