Bob Dylan definitely belongs in the list, and especially this album does. Very influential, has several major "hits" and some of the most covered songs ever. I mean, all on one album: Blowin' in the Wind, Masters of War, A Hard Rain, Don't think Twice! Dylan won't go into the history books as the best singer or harmonica player but that's not the point. His songwriting skills are the best and his legacy is clear. An easy 5 as a "must hear" album.