The major, together with the minor, are normally the first chord to learn for anyone who just starting out playing the guitar. These are fundamental and most other chord is expanded or altered versions of major or minor chords.
Besides the basic major chords there are other categories that also use major in the name. Among these are major seventh, major ninth and major thirteenth.
Basic major chords
The chord names
The basic major chords are often written with single letters as above. So the difference between C and C Major is, in this context, none. In some cases you may find these referred to as CM, DM, EM and so on. It's important if the "M" is uppercase and not lowercase, in the latter case a minor chord is intended.
There is in total twelve different basic major chords, one for every pitch. Less common is the five presented below. Because of the standard tuning of a guitar, the root notes C#/Db, D#/Eb, F#/Gb, G#/Ab and A#/Bb are often on less convenient positions in the fretboard (neither is any on an open string). Which makes them often harder to play and less common. (The five chords presented below are also often played as barre chords or with a capo).
Basic major chords with sharp or flat root
C# / Db
D# / Eb
F# / Gb
G# / Ab
A# / Bb
Theory of the major chords
A basic major chord always consists of three notes (or pitches). But since the guitar consists of six strings, some of the notes are unavoidably duplicated. The reason for this being the case sometimes and sometimes not is once again the instrument and its tuning. The G major is played on six strings, whereas the D chord is played on four only. In the case of D major, the cause is that the root note D, that should be played as the bass note, can't be found on the first three frets.
See also Chord progressions.
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