Zigbee is a low power consumption WiPAN (Wireless Personal Area Network). Zigbee is a protocol, similar to Bluetooth technology, which runs the WiPAN for low data rates. It is geared toward remote controlled technology to extend battery life. For example, the remote control at a podium or teaching station can use Zigbee to signal the drapes to draw down; dim the lights; send the projection screen down—all wirelessly. Other uses for Zigbee include intruder alarms, embedded sensing and automation in both home and industry. By its low power consumption it is meant to be a less expensive alternative to wired and wireless protocol.
Zigbee is self-organizing, meaning it works on a mesh-based network rather than the star or token ring. Zigbee can re-route itself if a network pathway is busy or blocked.
A wireless mesh network (from http://www.sensorsmag.com)
The advantage of Zigbee is clear in a retrofitting instance where installing new wiring would be costly and less time efficient. Control System companies such as AMX have created Zigbee enabled devices for building automation control and have plans for many future devices.
Zigbee has its limitations with low bandwidth communication and may not be the answer to all control requirements; however, low power consumption and self-healing connectivity make it a viable option for a wide range of applications. Check out http://zigbee.org for more info.