The flute is a transverse (or side-blown) woodwind instrument that is closed at the blown end and is played by blowing a stream of air over the embouchure hole. The pitch is changed by opening or closing keys that cover circular tone holes (there are typically 16 tone holes). Opening and closing the holes produces higher and lower pitches. The direction and intensity of the air stream also affects the pitch, timbre and dynamics.

The standard concert flute is pitched in C and has a range of about 3 and a half octaves starting from the musical note C4 (middle C). In most cases the flute's highest pitch is C7, however more experienced flautists are able to reach up to F7 (and in some cases C8). Modern flutes may have a longer foot joint (a B-foot), with an extra key to reach B3.