The major pentatonic scale relates to the major scale in the same way the
minor version of this scale relates to the relative minor scale. This scale is a
smaller, 5 note version of the major scale. The scale is usually used over a
major triad or power chord for a country or country rock type of sound. Use the
scale below over an A major triad, A power chord,, or a progression in the key
of A major that centers around an A major triad or an A power chord.
This type of scale is used sometimes in rock and metal. Not so
much, though.