So far we have learned the E, A and D major chords. A lot of Rock and Blues music tends to play the Power chord version of these chords to sound heavier and darker.
The upshot of this is the open power chords can be played with 1 finger, so they are really easy to play!! So lets take a look.
Notice that the root note (The lowest note of the chord) is the same compared to the standard major chord. But when played, these chords sound darker.
Remember, with power chords, you can play two or three strings without changing the sound much. This is because the extra note added is the octave of the lowest note, so you're just doubling up the same note but at a higher pitch. Either 2 or 3 string power chords are generally interchangeable and are the players choice.
Check out the songs Common People by Pulp and Johnny B. Goode at this level for examples of this!
Rock Power Chords short-course!
Check out these 2 video lessons for a short course showing how to get these easy chords sounding like AC/DC or Led Zeppelin - worth checking out especially for the electric guitarists among you!