ZigBee uses unlicensed frequency bands but operate at slower speed or data rates.
ZigBee: This communication is particular designed for control and sensor networks on IEEE 802.15.4 requirement for wireless personal area networks (WPANs), and it is a outcome from Zigbee alliance.
This communication level defines physical and (MAC) which is refereed to as the Media Access Control layers to manage many devices at low-data rates.
Television reduced the space between the war and the person watching the TV. When the media showed the intensity and the chaos of the war, it helped turn people against it.