A trumpet is a brass instrument commonly used in classical and jazz ensembles. The trumpet group contains the instruments with the highest register in the brass family. Trumpet-like instruments have historically been used as signaling devices in battle or hunting, with examples dating back to at least 1500 BC; they began to be used as musical instruments only in the late 14th or early 15th century. Trumpets are used in art music styles, for instance in orchestras, concert bands, and jazz ensembles, as well as in popular music. They are played by blowing air through nearly-closed lips (called the player's embouchure), 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 rectangular shape.