All right, I will tell you a little bit about power chords. The name is combination of power, because they sound pretty powerful. Actually, they are not really chords. Chords are 3 notes or more, but there are only 2 different notes.
The reason why this kind of method are so popular is that they are easy to use and they sound pretty cool. Power chords are easy to play just about anywhere on the guitar neck and really helpfully on the really fast part of the song.
POWER CHORD PATTERN:
That technique is really easy to play, and you don’t need to change positions of your fingers.
Put your fingers in playing position and start playing. In order to change the chord just move up or down in the fret board.
Barre chords are a type of guitar chords, where one or more fingers are used to press down multiple strings across the guitar fingerboard. Name of those chords comes from a French word barre, witch in English is bar. Bar, because the first finger shape is like bar over the entire fret.Barre chords’ primary purpose is to shift any of the open string chords an arbitrary number of half steps up the neck of the guitar; similar to the use of a capo.
Basically the barre chords are divided into two types: E shape and A shape. The name comes from the name of the open chords. E shape because besides your first finger, all the other fingers are shape like an open E, and the same thing for A shape barre chords. To change chord just move up or down on the fretboard like you do on power chord.