The guitar used woods for the various parts of the instrument. The back and sides of the guitar's body are usually built with East Indian or Brazilian rosewood.
The top and back of the guitar are formed in a process known as "bookmatching," by which a single piece of wood is sliced into two sheets, each the same length and width as the original but only half as thick. This gives the sheets a symmetrical grain pattern. The two sheets are matched to ensure continuity in the grains and glued together.
The neck, which must resist distortion by the pull of the strings and changes in temperature and humidity, is constructed from mahogany and joins the body between the fourteenth and twelfth frets. Ideally, the fingerboard is made of ebony, but rosewood is often used as a less expensive alternative. Most modern guitars use strings made of some type of metal (usually steel).
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