A type of string used on stringed instruments that has been manufactured from animal gut. The gut string dates back to ancient Greece. The gut comes typically from sheep (occasionally bull) intestines, although other animal gut has been used in certain areas in the world. It is a common misconception that strings are made of cat gut, but that has never been true. With modern technology, common practice is to use a stranded nylon string or steel strings for most stringed instruments, but before the late 1940's, gut and steel were the most common strings in use. There was evidence of some strings made from silk or horsehair in early music, but that was very uncommon. Gut strings are created from a complex process of soaking and drying the intestines until all of the flesh and membrane has separated from the strands of gut. The individual strands of gut are polished to remove bumps and then wound together to create each string. Thin strings may have two or three individual gut strands wound together and thick strings may be comprised of upwards of 120 individual strands of gut. The finished string is coated with oil to protect the gut. Around the 16th century, the thicker strings producing the lower pitches began to be wrapped in silver wire to protect the gut and create less mass. Many of the gut strings today have a gut core, but are wrapped in metal. Gut strings are fairly delicate and can easily break. They are also very sensitive to temperature and humidity changes, so they are more difficult to keep in tune. However, those performing Baroque and early music prefer to use the gut strings and keep as true to the period sound as possible. The sound of the gut string is warm and rich with complex overtones.