N.I.B. is heavy song from Black Sabbath's self titled debut album, which was released in 1970. This one has a very rhythmic power chord riff that's broken up by a high bend with a vibrato that rounds out the phrase. It has a call and response style of phrasing, where the riff plays the power chords (the call) and then are followed by the high bends (the response). There's a lot of rhythmic single string playing followed by extremely long droned power chords that create an atmospheric affect, which is a prime example of good song writing. It's important to know when the guitarist should lay back and not play so much, instead occupying a background role. The licks from the solo are incredibly melodic and incorporate a lot of major pentatonic shapes. There's a great 16th note lick that's a really good for beginners to practice their pentatonic playing and pull offs.