The harmonica is a musical instrument with wind and a free reed functioning on the same principle as the accordion: metallic reeds (lamellas) of different lengths, produce the notes by vibrating with the passage of the air, sucked or blown this Times by the mouth, this conjunction being infrequent for a wind instrument.

With a normal tessitura of three octaves, it is declined in three great families:

The simple diatonic harmonica;
The double diatonic harmonica (also called tremolo);
The chromatic harmonica.