The bansuri and venu are both Indian flutes, typically made of reed or bamboo. Both types of flutes are generally of the transverse variety, where the flute is essentially a short length of hollow bamboo or reed with holes cut into it. Flutes can sometimes be equipped with a fipple, a mouthpiece commonly used in woodwind instruments.
The bansuri is used in the North Indian style of music, which combines traditional Hindu music with Persian influences. Bansuri flutes traditionally have six holes although some newer flutes have seven. This extra hole offers more flexibility and can provide a more accurate pitch at higher registers. The bansuri was traditionally used exclusively in Indian folk music but has come to be used in such Indian genres as filmi sangeet -- a style associated with Bollywood movie musicals -- and classical Hindustani music.
The bansuri holds important religious and cultural significance to Indians of the Hindu faith as this flute is commonly associated with Lord Krisha. The bansuri is an ancient instrument with a long history and is referenced in the Vedas, the 3,000-year-old Hindu scriptures, as Lord Krishna's divine instrument. In fact, traditional Indian beliefs hold that the life force or pran ("breath") is converted into music through the bansuri.
The venu -- also called the Carnatic flute -- is a south Indian instrument associated with the Carnatic system of Indian music, a different-sounding, more sophisticated style than northern Hindustani Sangeet. In all but rare cases, the venu has eight holes. With both the bansuri and the venu, the transverse style is favoured by serious musicians, who consider the fipple varieties little more than toys.
Both the bansuri and the venu are side-blown instruments that require similar fingering techniques. Although the bansuri and the venu may look similar to the casual observer, the primary difference between the two is the number of holes each instrument has. The bansuri usually has six finger holes while the venu normally has eight. Another key difference is that the bansuri is primarily used in North Indian music, and the venu is heard in South Indian music.