The ocarina is a small, more or less egg-shaped wind instrument made of metal or earthenware. It is a type of duct flute in which the vibrations of air occur not in a tube but in a closed vessel, globular in shape. The name ocarina comes from the Italian for "little goose" and refers to the instrument's shape which is like that of a bird, without the head and neck. Ocarinas are most commonly made of porcelain, but also of wood, clay, metal, or plastic, and produce a rounded, plummy tone. Although European in origin, similar instruments, with a long history, are known in South America, among the Maoris of New Zealand, and in China.
The number of finger-holes varies from 5 to 12; the player blows into a small side air passage and sets up vibrations in the hollow body of the vessel. But the ocarina is unusual, for a flute, in that the pitch of the notes it produces doesn't depend on pipe length. The key factor in determining pitch is the total area of all the open holes divided by the hollow volume inside the instrument. Because of this, what matters is not the position of the holes but their size. The only caveat with regard to hole positioning is that holes placed too close to where the breath enters are not good because they tend to weaken the tone.