Chord Construction Theory
Please bear with me while I take care of just a few more theory points before getting to the heart of chord progressions. I do this because I would like us all to be on the same page in these discussions.
Anyway, I thought it was important to brush up on how chords are created:
In Part 1 we saw how scales were created, and chords come from scales. The "C" scale has the following notes:

C D E F G A B C
The positions of the notes of the scale are numbered:

Notes in a "C" major chord
To create a "C" chord we take the first, third and fifth notes of the scale ("C" "E" "G") to create the C major chord.

C D E F G A B C

Since there are three notes in the chord, this chord is called a triad. If we were to stack them up in order from lowest to highest notes (an impossibility on the mandolin due to its tuning) we would have a chord to play.

G
E
C

If we rearrange the notes in the chord stack to, say, "G" "E" "C", we have what is called an inversion:

C
E
G

That's why on guitar, mandolin, and other stringed instruments there are several different ways (shapes) to play a C major chord. We won't be concerned with much more about inversions until later. Suffice it to say it always good to learn several different spots on the instrument where you can play a given chord.

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