Bluetooth is a short-range wireless technology standard that allows data to be exchanged between fixed and mobile devices.
Originally invented by Ericsson in 1994, the technology uses short wavelength radio waves from 2.4 to 2.485 GHz.
It is managed by the Bluetooth Special Interest Group, which works to ensure interoperability across different platforms.
Unlike other forms of connectivity such as wi-fi or 4G, Bluetooth carries connections between devices and other devices as opposed to carrying data to and from the internet.
It is able to run at very low energy with Bluetooth Smart or BLE, making it ideal for devices that have to survive for long periods on a single charge. Devices that use forms of energy such as solar to power a Bluetooth connection are becoming increasingly common.
There is also a version of Bluetooth that allows very high quality data transfers, BR/EDR, allowing streaming at very high quality. This means that wireless audio has been a popular application for Bluetooth.