People are empathetic creatures. The human experience is highly contagious. We see others laughing or crying, smiling or yawning, and innately feel the urge to do the same. We have the uncanny ability to sense each others' emotions and they affect us in fascinating ways.
As the sun set on the last major analog recording format--the cassette tape--in the 90's, the world of recorded music began a shift into the digital realm. Nearly all music we hear today is through a digital medium--CD players, mp3 players, computers, and with good reason.