Theory: Chords of the Major/Minor Scales

Major Chord Progressions
If we take the major scale: C - D - E - F - G - A - B - C

And we build a triad off of each note of the scale using only notes found within the scale, we get this:

I C-E-G (1-3-5 Cmaj)
ii D-F-A (1-b3-5 Dmin)
iii E-G-B (1-b3-5 Emin)
IV F-A-C (1-3-5 Fmaj)
V G-B-D (1-3-5 Gmaj)
vi A-C-E (1-b3-5 Amin)
vii B-D-F (1-b3-b5 Bdim)
VIII C-E-G (1-3-5 Cmaj)

The major scale follows this whole-step/half-step pattern:
w - w - h - w - w - w - h

The chord scale follows the same pattern:
I ii iii IV V vi vii VIII
w w h w w w h

Now, all you have to do is remember which type of chord each number represents.

I ii iii IV V vi vii VIII
w w h w w w h
maj min min maj maj min dim maj

Minor chord progressions
Minor chord progressions are charted out much like major progressions, but the order of major and minor chords change.

i ii0 III iv v VI VII i
w h w w h w w

Types of chords
Minor chord: 1, 3b, 5 notes in the scale.

Major 7 chord: 1, 3, 5, 7 notes in the scale.

Minor 7 chord: 1, 3b, 5, 7b notes in the scale.

Dominant 7 chord: 1, 3, 5, 7b notes in the scale.

Diminished chord: 1, 3b, 5b, 6 notes in the scale.

Augmented chord: 1, 3, 5# notes in the scale.

6 th chord: 1, 3, 5, 6 notes in the scale.

Suspended chord: 1, 4, 5 notes in the scale.

Golden Progression
FYI, a very common chord progression is I-IV-V-I