Barre chords are a type of guitar chord where one or more fingers are used to fret (press down) several or all of the strings across the guitar fingerboard in order to play a chord not restricted by the tones of the guitar's open strings. Barre chords are often referred to as "moveable" chords, as they can be moved up and down the neck as needed. They are commonly used in most popular and classical music and are frequently used in combination with "open" or standard guitar chords. Frequently referred to as "jazz" chords, they are typically used for more complex chord voicings and playing in keys not suitable for the more basic open chords of the first position of a standard-tuned guitar.