Guitar Major Scale

The major scale is the most commonly used scale in Western music. It is a heptatonic (7-note) scale, synonymous with the Ionian mode, or diatonic scale. Used in every genre of music, this scale defines the core tones by which all scales in Western culture are labeled. The tones of the major scale are: R, M2, M3, P4, P5, M6, and M7. 

The intervals that make a linear major scale are whole step, whole step, half step, whole step, whole step, whole step, half step. In a C major scale, the intervals are C-D (W), D-E (W), E-F (H), F-G (W), G-A (W), and B-C (H). These intervals correlate to the white keys on a piano.  

In classic theory, each degree has a corresponding name: 1=Tonic, 2=Supertonic, 3=Mediant, 4=Subdominant, 5=Dominant, 6=Submediant, 7=Leading tone.  

The major scale is the basis for all diatonic modes. Each tone of the scale is associated with a corresponding mode name. For example, in the key of C, the scale tones are C,D,E,F,G,A,B. If you begin the C scale on the note D and play to the octave, this is the Dorian Mode. The D Dorian Mode is D,E,F,G,A,B,C; it uses the same notes as C major but starts on the 2nd tone. Likewise, the Mixolydian Mode is a scale using the C scale notes starting on its 5th degree: G,A,B,C,D,E,F.  

The names of the modes based on the scale tones are as follows: R-Ionian, 2-Dorian, 3-Phrygian, 4-Lydian, 5-Mixolydian, 6-Aeolian, and 7-Locrian. Though the modes are based on each corresponding scale note, the reality in music is that the modes serve functionally for the improvisor based on the underlying harmonic context. So, if you are improvising with the notes of the C major scale over a Dm chord, the mode would be considered the Dorian, regardless of the note you begin to improvise on. Likewise, if you used the same C major scale over a G7 chord, you would be using the Mixolydian mode. In practical playing, harmony determines modality. And modality in improvising cannot be determined well without any underlying harmony or determinative melodic patterns that outline the assumed underlying harmony. 

The major scale is also associated with corresponding triads. If you build triads above each scale tone by stacking notes in thirds, you come up with the same chord quality sequence for each scale tone. In C, with the base notes of C,D,E,F,G,A,B, the triads would be CEG, DFA, EGB, FAC, GBD, ACE, and BDF. The sequence of triads for every major scale is the same: Major, minor, minor, Major, Major, minor, and diminished.

So, for C major, the triads are C, Dm, Em, F, G, Am, and B diminished. In the key of G (with the scale G,A,B,C,D,E,F#), the triads would be G, Am, Bm, C, D, Em, and F#dim.  

The notes within the scale are considered diatonic notes. Notes outside of the scale are chromatic notes. Notes within the scale are either major or perfect. Notes outside the scale are minor, diminished, or augmented.

Since the major scale is the basis for all chords, scales, and harmony in Western music, it is an essential scale for all musicians to master. There is no more important scale in the world than the major scale (even though the pentatonic is perhaps a more used scale throughout the world) because all other scales are labeled based on this scale. This scale was the core of all tonal Western harmony until the late 19th/early 20th century, and it is still the most common scale basis for all composition.  

Since this scale has 7 notes, it has 7 modes and 7 positions on the guitar. Again, mastery of these 7 forms is essential, as it is the basis for all other understanding of scales and harmony.