The kazoo is a simple musical instrument that adds a "buzzing" timbral quality to a player's voice when one hums into it. The kazoo is a type of mirliton - a device which modifies the sound of a person's voice by way of a vibrating membrane. The membranophone label is a key element in the kazoo being called a musical instrument. Kazoos are often used by children because they are simple to use. For example near Forlì, in Italy, there exists a sort of mirliton made and used by children.