Chords are actually collection of notes being played at the same instant of time. In western music there are various types of chords. In our present explanation we will only focus on what are major and minor chords.
Major chord
A major chord consists of the 1st, 3rd and the 5th note of a major scale.
Let us take an example. Suppose for C major chord, the notes will be C E G as "C" is the 1st note, "E" is the third note and "G" is the fifth note of the C major scale : C D E F G A B C/
Similarly, D major scale will be :
D E F# G A B C# D/
Thus taking the 1st, 3rd and the fifth notes, ie:- D F# A, the D major chord consists of D F# and A.
In this way a basic major chord is formed.
Minor chord
A minor chord consists of the 1st, flat-3rd and the 5th note of a MAJOR scale.
Suppose let us take an example, the E major scale :-
E F# G# A B C# D# E/
Taking the 1st note, the flat-3rd note and the fifth note, ie:- E , G(as G is the flat note of G#) and B
Thus this forms the E minor chord : E G B
The C major scale :
C D E F G A B C/
Thus the notes of the C minor chord will be C D# G
The main point of difference between the major and the minor chord is, in major chord we take the 3rd note whereas in a minor chord, we take the flat-3rd note.
This is all about the major and the minor chord used in western music
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