The jaw harp, also known as the mouth harp, juice harp, or Jew's harp, is a unique and ancient musical instrument that is played by holding the frame against the teeth and plucking the metal tongue. It has been used by many cultures throughout history, and has various names depending on the region and language. In Germany, it is called a maultrommel, while in Russia it is known as a vargan. The French call it a guimbarde, and the Vietnamese refer to it as a dan moi. Despite its many names and variations, however, the jaw harp remains a fascinating and distinctive instrument with a rich history and enduring appeal.