Non-proprietary (open) standard for wireless digital data communication over short distances (10 meters/30 feet). A radio-frequency (RF) based technology, Bluetooth aims to connect virtually every type of electronic device computers, keyboards, monitors, printers, personal digital assistants, headphones, microphones, mobile phones, video cameras, etc. across walls and barriers without wires. It operates at a frequency of 2.45 GHz to give the current maximum data transfer rate of 1 megabits per second (up to 700 kilobits per second in practice, or more than 10 times the speed of a 56K modem), and employs 'channel hopping' techniques to reduce electromagnetic interference (EMI). Proposed in 1998 by Swedish electronics firm Ericsson (world's largest mobile systems supplier), Bluetooth is supported by some 2,000 companies world-wide, including IBM, Intel, Microsoft, Motorola, Nokia, Siemens, and Toshiba. Named after the 10th Century Viking king Harold Blatland (unifier of Dutch and Norwegian kingdoms) whose last name means bluetooth in old Norse. See also Wi-Fi.