What Is a Guitar Capo?
A capo clamps across the strings to raise the guitar’s pitch.
In simple terms
The capo acts like a movable nut. Each fret raises every open string by one semitone while you use familiar open-chord shapes.
Why guitarists use capos
A capo can place a song in a comfortable singing key, produce a brighter tone or make a progression easier to play.
How transposition works
A C chord shape with a capo on the second fret sounds as D. The shape stays the same, but the sounding chord moves up two semitones.
Where to place it
Position the capo just behind the fret, not directly on it. Use only enough pressure to make every string ring clearly.