The standard wireless network for short-range transmission of digital audio and data. Using radio waves, Bluetooth transmits through walls and other non-metal barriers. Although the term is synonymous with cellphone headsets and hands-free telephony in vehicles, Bluetooth is also used for wireless speakers, keyboards, mice, game controllers, smartwatches and more (for the different categories, see Bluetooth profiles
). Constantly enhanced, see Bluetooth versions
for version details.
Spread Spectrum Frequency Hopping
Bluetooth is a personal area network (WPAN) that continuously changes its frequency. It randomly changes to one of 79 channels 1,600 times per second in the same unlicensed 2.4 GHz band as Wi-Fi. See spread spectrum
Named after ancient King Harald Blatan of Denmark, Sweden-based Ericsson developed Bluetooth and co-founded the governing body in 1998 (www.bluetooth.com). Bluetooth is also an IEEE personal area network (PAN) standard (see 802.15
). Supporting point-to-point and multipoint architectures (see piconet
), there are billions of Bluetooth devices in use. See Bluetooth glossary
Bluetooth = Headset
Because they are were so ubiquitous, "Bluetooth" initially became synonymous with "headset." However, Bluetooth connects many other devices.
This "gamepad" from Sony uses Bluetooth to communicate with the PlayStation3 game console. See video game controller
. (Image courtesy of Sony Corporation.)
This Oral-B toothbrush sends elapsed time to the app in the user's smartphone via Bluetooth to monitor brushing time and history.
The stylized "B" displayed on a modern smartphone (left) or earlier cellphone (right) means that Bluetooth has been turned on in the device.