and tempered.) Some violin E strings are gold-plated to improve tone quality. Steel Steel or metal strings have become the foundation of strings for the electric guitar and bass. They have a pleasingly bright tone when compared to nylon strung guitars. Their metal composition varies greatly, sometimes using many different alloys as plating. Much of the history of metal strings evolved through innovations with the piano. In fact, the first wound metal strings ever used were used in a piano. However, when it came to getting super small diameter strings with good elastic properties, the electric guitar took the metal string to the next level adapting it for the use of pickups. Because of the higher tension of steel strings, steel-strung guitars are more robustly made than 'classical' guitars, which use synthetic strings. Most jazz and folk string players prefer steel-core strings for their faster response, low cost, and tuning stability. Nylon Nylon string, traditionally used for classical music, has a more mellow tone, and the responsiveness of it can be enjoyed typically for folk but other styles of music use it as well (for example, Willie Nelson performs on a nylon strung guitar). Nylon strings are made of a softer, less dense material and are under less tension than steel strings (about 50% less). This means they can be used on older guitars that can't support the tension of modern steel strings. Nylon strings do not work with magnetic pickups, which require ferrous strings that can interact with the magnetic field of the pickups to produce a signal. Currently, stranded nylon is one of the most popular materials for the cores of violin, viola, cello, and double bass strings. It is often sold under the trade name of Perlon. Nylon guitar strings were first developed by Albert Augustine Strings in 1947. Gut The intestine, or gut, of sheep, cattle, and other animals (sometimes called catgut, though cats were never used as a source for this material) is one of the first materials used to make musical strings. In fact, the Ancient Greek word for string, "khordḗ," has "gut" as its original meaning. Animal intestines are composed largely of elastomers, making them very flexible. But they are also extremely hygroscopic, which makes them susceptible to pitch fluctuation as a result of changing humidity. Exposure to moisture from the sweat of a musician's hands can cause plain (unwound) gut strings to