A Moodswinger, a strange type of string instrument with a movable rod under the strings

A string instrument is a musical instrument that makes sound by vibrating the strings on it. The strings are plucked or bowed to produce sounds. Each string has a different frequency. The desired frequency can be obtained by adjusting the tension on the string. The strings on these instruments usually come in many shapes and forms. There are many types of stringed instruments, the most common of these appearing in the Violin family.