In the Miles Davis 75th anniversary edition back cover you can read that this album change your life. I think simply a miracle: Miles Davis (trumpett), John Coltrane (who returned with Davis after a year working with Thelonious Monk) and Julian “Cannonball” Adderley (sax), Bill Evans and Wynton Kelly (piano), Paul Chambers (bass), Jimmy Cobb (drums). Five new tracks. Improvisation. Two sessions (march 2 and april 22,1959. Yes, this is a miracle, and I’m a believer 
I have no words to talk about this album. People with more knowledgment has written about it (in fact there is a good book: Kind of Blue: The Making of the Miles Davis Masterpiece by Ashley Kahn; you can read some Bill Evans notes). It’s not only a masterpiece of bebop, nor of jazz. It’s a masterpiece of music, and must be among Beethoven, Bach or Chopin opus.
If you are a beginner in jazz, I strongly suggest you hearing it.