A guitar's frets, fretboard, tuners, headstock, and truss rod, all attached to a long wooden extension, comprise its neck. Wood used to make the fretboard often differs from the rest of the neck.
The bending stress on the neck is considerable, particularly when heavier gauge strings are used , and the ability of the neck to resist bending is important to the guitar's ability to hold a constant pitch during tuning or when strings are fretted.
The rigidity of the neck with respect to the body of the guitar is one determinant of a good instrument versus a poor one. Conversely, the ability to change the pitch of the note slightly by deliberately bending the neck forcibly with the fretting arm is a technique occasionally used, particularly in blues and those derived from it, such as rock and roll.
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