Power chords get their name from the tight, powerful three-note chords that are heard in Rock and Metal music. Some of that power comes from the guitar’s amp of course but if you don’t use the proper technique and play with confidence, you won’t get that powerful sound.
The three notes (the three strings) used in these chords are either the sixth, fifth and fourth strings or the fifth, fourth and third Power Chords strings. In the case of a G chord, your first finger is on the sixth string, 3rd fret, your ring finger on the fifth string, 5th fret and your pinky plays the fourth string on the 5th fret. Like all three finger chords, these are the only strings played. Note: you may have a hard time extending your ring and middle fingers far enough to play all three strings of a power chord. If so, don’t be discouraged. It takes a little time to get your fingers to stretch out in this way.
How they are named. In the G chord mentioned above, the first finger is playing the note G (sixth string, 3rd fret) and that is the name of the chord. Starting a power chord on the six string, 5th fret is an A power chord and using the power chord shape with your first finger on the fifth string, 2nd fret, creates a B chord. The name of the chord is the same as the note your first finger is playing so it’s a good idea to learn the names of the notes on the fretboard.
We’ll begin with the guitar strings. Each one has its own specific ranking number. Beginning with the thinnest one at the bottom we have the 1st string. And when you go up you have the 2nd string, the 3rd, the 4th, the 5th, and finally (the thickest one) the 6th string.
And then we have the guitar neck separate by frets and spaces. The one at the far end of the neck where the tuning keys are found is the first fret (or first space). And you go all the way up to the guitar body. So the closest you are to the guitar body, the higher the number is.