Released in 1999, Bluetooth is a wireless technology standard that allows for short-range data transfer between devices. Bluetooth data is divided into smaller packets and travels via short-wavelength UHF radio waves. Although Bluetooth devices pledge to keep connections stable at distances of at least up to ten meters, the maximum effective range depends on variables related to each linked device and their surroundings.
It all started with headsets, as Nils Rydbeck (CTO at Ericsson Mobile) and physician Johan Ullman, alongside other scientists, started working on a "short-link" radio technology in 1989. The group's goal was to develop wireless headsets. Ten years passed until the first consumer Bluetooth device hit the market; today, wireless headsets are everywhere, and their popularity keeps rising.
Bluetooth is also a user-favorite feature for wearable devices. The technology makes things considerably easier for consumers, as data can be automatically synced between the wearable and a smartphone, also making it possible to read messages and take calls (among other possibilities) with the wearable.
Bluetooth standards are managed by the Bluetooth Special Interest Group (SIG). Established by Ericsson, IBM, Intel, Nokia, and Toshiba, the SIG is associated with over 30,000 companies that market a broad spectrum of products: from smartphones and other consumer electronics to robotics systems and hearing aids. The technology has a wide variety of applications, such as file transfer, wireless control, and communication between devices (like a smartphone and a car stereo system, or a game console and wireless controllers), as well as audio streaming and communications with devices such as GPS receivers and bar code scanners.
When connected, Bluetooth devices are categorized as "slave" and "master," but these roles may shift depending on the direction of the connection. Master devices can communicate with up to seven other devices, although this number depends on the master's type, model, and usage. For security purposes, the user must authorize Bluetooth connections in a process known as "pairing." Once two devices have been paired, further connections may happen without the need for user action, and this prior authorization may be suspended at any given time.
Bluetooth technology has evolved considerably since its introduction, with each generation being listed under an ascending number per SIG standards. The latest Bluetooth generation, Bluetooth 5, was introduced on June 16, 2016. Novelties include trade-offs of twice the speed at a reduced range in low-energy mode (BLE), or four times the range at reduced data transfer rates, among other new usage possibilities.