tuning

Guitar tunings assign pitches to the open strings of guitars, including acoustic guitars, electric guitars, and classical guitars. Tunings are described by the particular pitches denoted by notes in Western music. By convention, the notes are ordered from lowest-pitched string (i.e., the deepest bass note) to highest-pitched (thickest string to thinnest).Standard tuning defines the string pitches as E, A, D, G, B, and E, from lowest (low E2) to highest (high E4). Standard tuning is used by most guitarists, and frequently used tunings can be understood as variations on standard tuning. One mnemonic for this standard guitar tuning is Eddy Ate Dynamite, Good Bye Eddy.
The term guitar tunings may refer to pitch sets other than standard tuning, also called nonstandard, alternative, or alternate. Some tunings are used for particular songs, and might be referred to by the song's title. There are hundreds of such tunings, often minor variants of established tunings. Communities of guitarists who share a musical tradition often use the same or similar tunings.

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