Stand on any street in your town and you'll witness a trend that began 30 years ago with the invention of the Walkman: music lovers walking around wearing headphones.
The freedom to listen to the music of your choice without being tethered to a stereo changed the way people listened music. Consequently it also changed the way they performed daily tasks. Teenagers stuck in the backseat of the family van on vacation weren't forced to listen to oldies, and jogs through the park now came with a motivational soundtrack.
Today, those clunky players have evolved into credit card-sized digital music players, and you can't go two minutes without running into someone listening to their headphones. You're probably one of them.