The tambura is a musical instrument used in various places around the world.
India
A tambura (South India; North India: tanpura) is a long-necked Indianlute, unfretted and round-bodied. It has four or five (rarely: six) wire strings all played open which are plucked one after the other to make a drone sound.
In Hindustani classical music, with four strings, the strings are usually tuned PA SA SA SA, the last SA low. With a fifth string, NI is added: PA NI SA SA SA, the last SA low again (see swara).
Since the Tambura is an instrument of drone-accompaniment, it is incapable of playing melodies.
A Tambura is also a bulgarian long necked, fretted, bouzouki-like string instrument that comes in two styles 8-string (4 pairs) and 4-string (2 pairs), played with a plectrum.