First of three Step Scales,  Melodic Minor and Neapolitan Major being the other two.

Has Major, Major-Minor, Minor, and Diminished qualities

Establishes Tonic, Dominant, and Subdominant expectations

Equivalent definitions:

The major scale consists of…

• seven keys
• seven chords
• seven modes
• the Ionian Mode and it’s 6 permutations.
• 6 perfect fifths and 1 tritone.
  

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  First mode of Major Scale
  Maj1, Cmaj, Ionian

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  Second mode of Major Scale
  Maj2, Dmin, Dorian

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  Third mode of Major Scale
  Maj3, Emin, Phrygian

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  Fourth mode of Major Scale
  Maj4, Fmaj, Lydian

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  Fifth mode of Major Scale
  Maj5, Gdom, Myxolydian

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  Sixth mode of Major Scale
  Maj6, Amin, Aeolian

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  Seventh mode of Major Scale
  Maj7, Bdim, Locrian

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