Classic rock bands like the Beatles, Rolling Stones, Steppenwolf, and The Eagles still enjoy huge popularity today, even through their songs were recorded 30 to 40 years ago. These classic rock bands have endured the test of time because their songs were a new genre and were relevant toward the tumultuous times during which they were written and recorded, and the themes behind the songs are still active today.
Some of the most beautiful love songs and ballads came from the 60's and the 70's, and these classic rock bands broke a lot of social taboos against questioning authority, speaking out about feelings on a truly personal and honest level. Without this form of honesty and sensitivity, the classic rock bands we know today might have been forgotten.
There are numerous web sites that show the top 100 songs from these classic rock bands, and the about.com website has compiled the lists from all the good sites, and published the definitive list of top 500 classic songs. It's worth going to if classic rock bands interest you, and you enjoy their music. The web site also includes a link to each song that gives its history.