The modern flute is an instrument conceived in the nineteenth century by the Bavarian flautist and builder Theobald Bohem.
Over time it has acquired contributions from other flutists and builders including the Italian virtuoso Giulio Briccialdi who designed the B flat key, and the closed G key (which Boehm preferred opened).
The instrument is divided into three parts: headjoint, body and footjoint.
In the body and in the foot of the flute there is a mechanism that controls the opening of the holes. The standard construction includes 16 or 17 holes. The width of the holes increases down towards the foot. The tone holes can be extruded and edged (by machine) or built separately and welded to the pipe (soldered tone holes)
The mechanics is designed to organize an effective system of fingerings that allows the nine fingers used by the performer to control all 16 or 17 holes.
The mechanics can be composed of isolated keys (such as the B3, the G sharp and the D sharp) but most of the keys have the arms gathered in long rods inside which there are long common pivots. Rods and pivots are supported by small columns fixed on reinforcing plates welded to the flute tube. Inside the colums there are pin springs that have the task of returning the keys to their starting position when they are not activated.
The keys pressed directly by the fingers, may appear in a closed or even open form, ie perforated in the center. In this way you have flutes with a closed keyboard or open keyboard (this last version is more professional as it allows the execution of glissatos, microtones and multi-frequency sounds).