The flute is a musical instrument of the woodwind family. Unlike woodwind instruments with reeds, a flute is an aerophone or reedless wind instrument that produces its sound from the flow of air across an opening. According to the instrument classification of Hornbostel-Sachs, flutes are categorized as edge-blown aerophones.
A musician who plays the flute can be referred to as a flute player, a flautist, a flutist, or less commonly a fluter.
Aside from the voice, flutes are the earliest known musical instruments. A number of flutes dating to about 40,000 to 35,000 years ago have been found in the Swabian Alb region of Germany. These flutes demonstrate that a developed musical tradition existed from the earliest period of modern human presence in Europe.
In its most basic form, a flute can be an open tube which is blown like a bottle. There are several broad classes of flutes. With most flutes, the musician blows directly across the edge of the mouthpiece. However, some flutes, such as the whistle, gemshorn, flageolet, recorder, tin whistle, tonette, fujara, and ocarina have a duct that directs the air onto the edge (an arrangement that is termed a "fipple"). These are known as fipple flutes. The fipple gives the instrument a distinct timbre which is different from non-fipple flutes and makes the instrument easier to play, but takes a degree of control away from the musician.
Another division is between side-blown (or transverse) flutes, such as the Western concert flute, piccolo, fife, dizi, and bansuri; and end-blown flutes, such as the ney, xiao, kaval, danso, shakuhachi, Anasazi flute, and quena. The player of a side-blown flute uses a hole on the side of the tube to produce a tone, instead of blowing on an end of the tube. End-blown flutes should not be confused with fipple flutes such as the recorder, which are also played vertically but have an internal duct to direct the air flow across the edge of the tone hole.