Rattles are found in almost every musical culture, in almost every era throughout human history. Technically, they are classified as idiophones, but that simple label does not convey the almost overwhelming variety of materials from which they are made or performance contexts where they are used. Rattles can be made from animal horn or hide, leather strips, rope, cloth, wood, nut shells, gourds, metal, or clay. They can be filled with shell, stone, corn kernels, beads or other sound-producers. They can be held in the hand and shaken or struck against a hard surface. They can be tied around the wrists, waist or ankles or attached to other musical instruments, such as drums or xylophones.

There is at least one constant feature in this incredible diversity of form and use: almost without exception, rattles accompany dancing as well as vocal music. In English, their very name suggests movement, articulating the melodic rhythm and adding a shimmering, buzzing sound quality to the music.