This was the first Zappa/Mothers of Invention album I ever bought, way back in 1969. I literally learned how to play lead guitar by playing along with this album, which I still have. It exposed me to the possibilities of "rock" music that goes far beyond what I was into at the time (Beatles, Stones, Hendrix, Cream, Blind Faith, etc.). It opened up my ears and my mind  to all the musical possibilities, including a twisted sense of humor, often lacking during much of the late Sixties music scene (think Doors and Jefferson Airplane - deadly serious bands).