Have been looking for my Mac an external hard drive. My main criterion was the volume. For this I got myself three of the quietest 2.5-inch external hard drives. This, WD My Passport, Toshiba HDTD210ESMEA. According to current standards, all three drives are considered quiet. I distinguish between softly, very softly and inaudibly. The last two I would classify in my (of course, purely subjective) assessment than just quietly. And that even with good will. The Samsung drive but was noticeably quieter. Not silently! Operational. In the resting state was hardly a sound to be heard with the ear hook. Respect. That no one has ever managed. So: quiet operation (rigorously) and almost inaudible in idle mode. Toll. As a die-hard Apple fan I salute Samsung. One more thing: I want to take a brief reference to two reviews. I use the external hard drive as an external hard drive. Not as internal. Would I need an internal hard drive, I would resort definitely to an internal hard drive. For I have heard that the body of the external hard drive is hard to open. : O)