Claim: One style of the mandolin is the flat-backed mandolin.

A mandolin -LRB- mandolino -LSB- mandoˈliːno -RSB- ; literally `` small mandola '' -RRB- is a musical instrument in the lute family and is usually plucked with a plectrum or `` pick '' . It commonly has four courses of doubled metal strings tuned in unison -LRB- 8 strings -RRB- , although five -LRB- 10 strings -RRB- and six -LRB- 12 strings -RRB- course versions also exist . The courses are normally tuned in a succession of perfect fifths . It is the soprano member of a family that includes the mandola , octave mandolin , mandocello and mandobass .   There are many styles of mandolin , but three are common , the Neapolitan or round-backed mandolin , the carved-top mandolin and the flat-backed mandolin . The round-back has a deep bottom , constructed of strips of wood , glued together into a bowl . The carved-top or arch-top mandolin has a much shallower , arched back , and an arched top -- both carved out of wood . The flat-backed mandolin uses thin sheets of wood for the body , braced on the inside for strength in a similar manner to a guitar . Each style of instrument has its own sound quality and is associated with particular forms of music . Neapolitan mandolins feature prominently in European classical music and traditional music . Carved-top instruments are common in American folk music and bluegrass music . Flat-backed instruments are commonly used in Irish , British and Brazilian folk music . Some modern Brazilian instruments feature an extra fifth course tuned a fifth lower than the standard fourth course .   Other mandolin varieties differ primarily in the number of strings and include four-string models -LRB- tuned in fifths -RRB- such as the Brescian and Cremonese , six-string types -LRB- tuned in fourths -RRB- such as the Milanese , Lombard and the Sicilian and 6 course instruments of 12 strings -LRB- two strings per course -RRB- such as the Genoese . There has also been a twelve-string -LRB- three strings per course -RRB- type and an instrument with sixteen-strings -LRB- four strings per course -RRB- .   Much of mandolin development revolved around the soundboard -LRB- the top -RRB- . Pre-mandolin instruments were quiet instruments , strung with as many as six courses of gut strings , and were plucked with the fingers or with a quill . However , modern instruments are louder -- using four courses of metal strings , which exert more pressure than the gut strings . The modern soundboard is designed to withstand the pressure of metal strings that would break earlier instruments . The soundboard comes in many shapes -- but generally round or teardrop-shaped , sometimes with scrolls or other projections . There is usually one or more sound holes in the soundboard , either round , oval , or shaped like a calligraphic -LRB- f-hole -RRB- . A round or oval sound hole may be covered or bordered with decorative rosettes or purfling .