The banjo is a plucked, stringed instrument. It has a
round body with an open back. It is made of a
wooden circular hoop with a skin or vellum stretch over it. The neck is fretted
like a guitar, and it has five metal strings. The leftmost string is shorter
than the others, and is fretted with the thumb, and tuned to the G above middle
C ( G4 or midi note number 67).
The other 4 strings from left to right, are tuned to C below middle C, G below middle C, B just below middle C, and D above middle C.
The banjo originates from Africa, and was brought to the United States in the 17th century by black slaves. It was adopted later by white musicians in minstrel shows, and is now popularly used in some traditional jazz bands, some American folk music, and commercial "Blue-Grass" bands.