As stated in the Chord Formulas tutorial, all chords are based on the Major Scale (W-W-H-W-W-W-H).

In that tutorial, we also learned how to find the notes of an A Major Chord (A - C# - E).

Here are the notes of the A Major Chord ( A - C# - E ) on the A(5th) string.

Major and Minor 3rd intervals are terms used to tell how distant the 2 notes are from each other.

A Major 3rd interval is 2 steps (4 frets) from the previous note.

A Minor 3rd interval is a step and a half (3 frets) from the previous note.

If we look at the 3rd of the A Chord, the C#, it is 4 frets from the previous note,

which is the number of frets from the ROOT A, to the C# 3rd.

This is called a Major 3rd interval

If we look at the 5th of the A Chord, the E, it is 3 frets from the 3rd, C#.

which is the number of frets from the ROOT A, to the C# 3rd.

This is called a Minor 3rd interval

A Major chord is designed with a Major 3rd interval, and a Minor 3rd interval.

In the case of the A Major Chord, the A to C# is a Major 3rd interval,

and the space between the C# and the E is a Minor 3rd interval.

Understand that in these terms, we are talking about intervals(the distance between the notes),

not the positions in the chord. The Major 3rd interval (4 frets), and Minor 3rd interval (3 frets).

In the case of an A Minor (Am) Chord, the A to C is a Minor 3rd interval,

and the C to the E is a Major 3rd interval.

The 7th interval of the Major Scale is a Diminished Chord. A Diminished Chord consists of 2 Minor Intervals.

In the C Major Scale, the 7th interval is B. The notes of the B Diminished Chord are B - D - F

The distance from B to D is 3 frets, or a Minor 3rd. D to F is also 3 frets, or a Minor 3rd.

Diminished Chords are simply a Minor 3rd + a Minor 3rd.

This short tutorial showed the different intervals between notes of a chord.

The Minor 3rd interval is a step and a half (3 frets) from the previous note,

while the Major 3rd interval is 2 steps (4 frets) from the previous note.

A Major chord is made up of a Major 3rd interval, followed by a Minor 3rd interval

A Minor chord is made up of a Minor 3rd interval, followed by a Major 3rd interval.

A Diminished chord is made up of a Minor 3rd interval, followed by another Minor 3rd interval.