Blue-tooth it’s technology which is create communication between two Bluetooth enable device without wair. Bluetooth operators work with 2.4 Ghz. Spectrum to create a wireless link between 2 devices using 
the same standard. Blue-tooth is designed to replace the wires in our lives & define our personal area network (PAN). That means it’s all about synching your PDA without a cradle, using your cell phone as a modem without using a cable & printing without a physical connection with printer.
The key with blue-tooth is that it’s supposed to automatically identify enabled devices within 30 feet. Unlike most networking standards that require some configuration, blue-tooth theoretically require none. Some authentication is required, so strangers won’t be able to use your device without permission.