Guitar chord in the abstract musical-theory of chords for all instruments. For example, in the guitar (like other stringed instruments but unlike the piano), open-string notes are not fretted and so require less hand-motion. Thus chords that contain open notes are more easily played and hence more frequently played in popular music, such as folk music. Many of the most popular tunings—standard tuning, open tunings, and new standard tuning—are rich in the open notes used by popular chords. Open tunings allow major triads to be played by barring one fret with only one finger, using the finger like a capo. On guitars
Standard tuning a standardized tuning system (see page). Standard tunings in plucked string instruments cover many different instruments which are plucked either by the fingers or with a plectrum. Guitars and bass guitars have more standard tunings, depending on the number of strings an instrument has: Guitar notation is an octave above the actual note, so Middle C (C) in guitar notation is the third space on the treble clef, whereas the note written as one line below the treble clef is C. Guitars are thus normally tuned in fourths, with the exception of a major third between the 2nd and 3rd