In the previous section we looked at how major scales are made up of a sequence of whole and half steps. That every major scale has a half step between notes 3 - 4 and 7 - 8. If you move the root note you need to also move the sequence of whole and half steps. Also, that while a major diatonic scale based on the note C has no sharps or flats, if you move the root note up to D both the F and C notes have to be sharp for the sequence to be correct.
But what would happen if we played the notes from D to D but this time we played just the white keys -the notes that make up the C major scale? This would force the sequence of whole and half steps to change and in doing so would construct a completely different scale. Scales that are made up like this, using the notes of a major diatonic scale but starting on a note other than the root, are called modes. Modes are nothing more than a variation of the sequence of whole and half steps.Let's take a closer look at this.
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