This exercise is from the Theory Section on Chords - an introduction to Keys. Go there to learn more about the progression we are playing through here, and why.

Here we play out the chord triads we get from the E Major scale, and later expand these triads into full barre chords.

E Major scale: E - F# - G# - A - B - C# - D# - E

1 - 3 - 5 = Chord Triad
E - G# - B = E Major
F# - A - C# = F# Minor
G# - B - D# = G# Minor
A - C# - E = A Major
B - D# - F# = B Major
C# - E - G# = C# Minor
D# - F# - A = D# diminished
E - G# - B = E Major

Like last time with the triads derived from the C major scale, you can probably see that there are also 2 main triad shapes here for the E major and minor chords. Leaving the diminished for now, you should notice that the majors have one triad shape and the minors have another shape. Again it is only the middle note (this is the 3rd which determines whether the triad is major or minor) that changes position.

After watching the triads, you should see the barre chords for each chord cycle through the same progression:

E Major - Open chord, the rest are barre chords...
F# Minor
G# Minor
A Major
B Major
C# Minor
D# diminished
E Major

Notice that the triads played in the first part of the ActionTab are really just a part of the larger barre chord! The barre chords shift up through the chord progression - the difference is only in whether a Major Barre Shape is used or a Minor Barre Shape. Again, the only difference between the major and minor barre shapes is whether that 3rd is major or minor (played with 2nd finger on G string, or with 1st finger).

If you don't know what barre chords are then go to here to learn more.

So, to quickly work out which chords are in the key of any scale - just find the root note on the Low E string. Now play E shape barre chords from that position in the following order:

Major - Minor - Minor - Major - Major - Minor - Diminished - Major

Remember to follow the major scale intervals:

root - 2 - 2 - 1 - 2 - 2 - 2 - 1

Do that with your first finger on the Low E string as you form the chords, and you can quickly find every chord related to the key you are playing in!

Try working out the chords from other key scales like this and over time you will not just begin to learn your chords, but you will get a feel for which chords work with different keys. This becomes very useful when constructing your own music, or soloing on the fly!