Metal stem attached to an automobile. Often used in conjunction with car stereos to receive radio waves. While single-piece car antennas were the de facto standard for many years, manually, and more recently automatically retractable car antennas have become all the rage. Car antennas are not limited to simply receiving AM and FM radio broadcasts, occasionally they are set up in conjunction with other electronic devices to receive CB, Police Band, Cell Phone, Wireless Internet, and, for the elite, TV signal. At one time GM actually took the technology to an unforeseen level by embedded car antennas within the windshield. The public was apparently not ready for it.