This turns your MP3 player or phone into a time machine, letting you hear the evolution of the guitar solo and the drum kit.

Rock and roll isn't just a genre; it’s a cultural earthquake that reshaped the world. From the distorted blues of the 1950s to the grunge-soaked 90s and beyond, the "greatest" songs are the ones that defined generations. Whether you are looking to build a digital library or simply rediscover the hits, here is how to approach the ultimate collection of the 500 greatest rock and roll songs. The Pillars of the Rock Canon

For most listeners, streaming is the new "downloading."