Rockin' In Time by David Szatmary

This is an historical look at the social backdrop behind the various eras in rock and roll.  It looks like a book that wouldn't have much substance (something about the way it is published just makes it seem cartoonish rather than academic), but it is really very good.  The parts that are best relate to the aspects of the political, social, and economic factors that drive change, interwoven with the technical advances that contributed to the changes in rock and roll over time.  I have never studied the history of music, but I have been alive through much of the time that rock has been around, so it was particularly enlightening to me just how things link with each other, and how genres of music rise and fall over time.  Very well worth the time to read if you are interested in music, and goes all the way up to the 21st century when things like Spotify and straming music may make things like the album cover a complete historical phenomenon rather than the pop art of our time.