There is usually one or more sound holes in the soundboard, either round, oval, or shaped like a calligraphic In 1787 Luigi Bassi played the role of Don Giovanni in Mozart's opera, serenading a woman with a mandolin.
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.
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 (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.
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.
; literally "small mandola") 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 (8 strings), although five (10 strings) and six (12 strings) course versions also exist.
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.
Each style of instrument has its own sound quality and is associated with particular forms of music.