There is more than one style of the mandolin.
Mandolin . 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 . Other mandolin varieties differ primarily in the number of strings and include four-string models ( tuned in fifths ) such as the Brescian and Cremonese , six-string types ( tuned in fourths ) such as the Milanese , Lombard and the Sicilian and 6 course instruments of 12 strings ( two strings per course ) such as the Genoese .