Bluetooth has found its way into many devices ranging from personal computers to cell phones. The nearly ubiquitous technology is said to have been named after King Harald Bluetooth, who ruled Denmark in the 10th century.
Bluetooth operates in the 2.4 Gigahertz band.
Bluetooth signals typically travel over a distance of 10 to 300 feet. Because Bluetooth uses radio frequencies, the devices do not have to be within line of sight of each other.
Bluetooth was developed in 1994 by Jaap Haartsen and Sven Mattisson while they were working for Sony Ericsson in Sweden.
Bluetooth frequencies are shared by cordless phone and Wi-Fi devices. To limit the effects of interference, Bluetooth uses frequency-hopping technology. This shifts the Bluetooth frequency in 1 Megahertz increments across the 2.4 to 2.485 Gigahertz-alloted bandwidth to a point where interference is lowest.
Class 1 Bluetooth devices have an effective range of 300 feet. Class 2 devices have an effective range of 33 feet. Class 3 Bluetooth devices have an effective range of 3 feet.
Bluetooth frequencies allow data rates of up to 24 Mbps when using Bluetooth 3.0. Future technological advances might increase this rate further.