History of ZIGBEE Technology

ZigBee-style networks began to be conceived about 1998, when many engineers realized that both WiFi and Bluetooth were going to be unsuitable for many applications.

In particular, many engineers saw a need for self-organizing ad-hoc digital radio networks.

The IEEE 802.15.4 standard was completed in May 2003.
The ZigBee specifications were ratified on 14 December 2004.
The ZigBee Alliance announces public availability of Specification 1.0 on 13 June 2005.