Miscellaneous Systems 323 down automatically when not in use to minimize energy consumption. Data rates range from 1 to 3 Mb/s depending on the version of Bluetooth device. The versatility of Bluetooth technology is its most appealing feature. Computer users can use Bluetooth to network between computer and for using a printer, mouse, and keyboard between computers. Bluetooth can also replace the traditional type of serial connections in commercial and medical applications GPS Definition GPS means Global Positioning System, and it refers to a way of locating position on Earth by using signals from two or more satellites. The system makes use of 24 satellites that orbit the earth in predictable paths at around 177,000 km (11,000 miles) above the Earth. This number of satellites, and the orbits chosen, ensure that at least four satellites (usually eight) will be within the line of sight for a receiver anywhere on Earth. By using information from three satellites, the latitude and longitude