Have you ever had the experience of being somewhere away from the noise of a big city? Perhaps on a mountain somewhere, on a desert, and as you set and looked up at a starry sky, you were absolutely amazed at the silence. It was quiet, right?

Not exactly. It wasn't quiet, it was simply that you couldn't hear the sounds. Strange but true is the fact that the atmosphere around us is filled with a thousand voices, but you're not tuned to them. You don't pick them up. If somebody should ask, "What kind of a device are you listening to?", perhaps you would say, "Well, it's a radio," or  "I'm listening online, over the internet." There are voices, sound waves, cellular and digital signals all around us.