A trumpet is a musical instrument. It has the highest register in the brass family. As a signaling device, trumpets have a very long history, dating back to at least 1500 BC; they have been used as musical instruments since the 15th century. They are played by blowing air through closed lips, producing a "buzzing" sound that starts a standing wave vibration in the air column inside the instrument. Since the late 15th century they have primarily been constructed of brass tubing, usually bent twice into a rounded oblong shape.