In spite of the name, Bluetooth is not a second-string pirate captain or a particularly bizarre dental malady. It is, in fact, a short-range wireless communications technology. The original Harald Bluetooth was a tenth-century Danish king who united parts of Norway and Denmark into a single Viking kingdom. Modern Bluetooth technology was named in his honor because it was intended to unite the worlds of portable computers and mobile telephones. Today, Bluetooth has become an industry standard for wireless connections among computers, printers, and other peripheral devices, along with mobile phones, headsets, and even wearable items with built-in wireless data exchange.
In general, Bluetooth is intended to replace wired connections between electronic equipment. Ultimately, the designers of Bluetooth hoped to completely replace the confusing tangle of wires and cables behind many computers with a single wireless interface module. More important, Bluetooth makes it possible to use external peripherals (including keyboards, mice, and printers) or transfer data to a computer without the need to find and attach a cable first.
Bluetooth is used for many kinds of wireless connections, including:
Connecting a keyboard and mouse to a computer
Connecting one or more computers to a printer
Connecting a cordless telephone to a base station or a computer
Connecting a mobile telephone or PDA to the Internet
Connecting two computers or a computer and a handheld PDA, for data transfer
Connecting to a Personal Area Network (PAN)
Connecting a headset or earpiece to a mobile telephone
Connecting headphones to a computer, a stereo, or other home entertainment system
Bluetooth's maximum data transfer speed is only 700 Kbps, which is a lot slower than some other wireless data transfer technologies, so it's not the best choice for every application. It's fine when you want to connect one or more peripheral devices to a computer, but not as a replacement for high-speed Ethernet or WiFi connections.
Because Bluetooth uses radio signals that can interfere with medical equipment and aircraft navigation systems, it's best not to use it in certain situations. Therefore, it's always a good idea to carry cables or alternative, non-Bluetooth devices (such as a headset that connects to your computer through a cable) that you can use in places where you can't use a Bluetooth connection.