What is Bluetooth?
Bluetooth™ refers to an open specification for a technology to enable short-range wireless voice and data communications anywhere in the world. The Bluetooth SIG (Special Interest Group) is an industry group, driving the development of the technology and bringing it to market. The founding SIG members are Ericsson, Intel, IBM, Nokia, and Toshiba.

About the Technology
Bluetooth uses the 2.40 to 2.48 GHz ISM (Industrial, Scientific, Medical) band, which provides unlicensed radio frequencies. As the frequencies are unlicensed and are available in most areas of the world, virtually anyone can set up Bluetooth coverage in almost any area. Bluetooth uses spread spectrum, frequency hopping, full-duplex signal at a rate of 1600 hops/sec with the range of about 10 meters to around 100 meters radio link which can transmit a maximum capacity of 720 kilobits per second per channel.

The signal hops among 79 frequencies at 1 MHz intervals to give a high degree of interference immunity. The RF output of a Bluetooth device is specified as 0 dBm (1 mW) in the 10m-range version and -30 to +20 dBm (100 mW) in the longer range version.

Bluetooth Applications             
Bluetooth is designed to operate in an environment of many users. Up to eight Bluetooth devices can communicate in a small network called a piconet. Multiple piconets can coexist in the same coverage range of the Bluetooth radio. To provide security, each link is encoded and protected against eavesdropping and interference.
 Bluetooth provides support for three general application areas using short-range wireless connectivity:
Bluetooth facilitates real-time voice and data transmissions by providing effortless wireless connection of portable and stationary communications device A device equipped with a Bluetooth radio can establish instant connection to another Bluetooth radio as soon as it comes into range. Bluetooth eliminates wires and cables between both stationary and mobile devices. For Further information refer to www.bluetooth.org