Blue tooth is a telecommunications device for wireless personal area network which describes how mobile phones, computers, laptops, printers, video game consoles and digital camera can be interconnected using a short range wireless connection. With the help of this technology, users of cell phones, personal digital assistants and pagers can get synchronized with information and have all mobile and computer devices be fully coordinated. The term blue tooth derived its name from a tenth century Denmark king Herald blue tooth Blatand who united Denmark and Norway and was famous for his ability to help people to communicate with each other.

To include blue tooth facility, a low cost transceiver chip must be included in each device, which transmits and receives in an unused frequency band available globally.

Blue tooth enables short-range wireless connections between desktop and laptop computers and a host of other peripheral devices for worldwide compatibility on an internationally available frequency band.

Since blue tooth uses radio waves in 2.4-gigahertz range, it is designed such that it is a safe and inexpensive way of connecting and exchanging information between devices without wires. Since it uses a common protocol, transmission of data between two blue tooth devices from various manufacturers would be straightforward. If the mobile phone has blue tooth hardware, blue tooth drivers are not necessary because the software is inbuilt and ready for use. Then blue tooth can be used to beam the photos and other objects from the mobile phone to the laptop or a PC provided the PC also has the blue tooth.

Blue tooth and wi-fi are both radio technologies but the frequencies and protocols are different and both of them are not compatible on the same device. The speed and the power of a blue tooth are lower than that of wi-fi. To pair one blue tooth device to another, a pass code must be exchanged between the two devices. While connecting the first, it asks for a 4-digit pass code and then the other device asks for the pass code where the same pass code must be given.

There are many advantages and disadvantages of blue tooth. Since it is a wireless device, there is no need for connection cables and can be used while traveling also. Blue tooth is inexpensive and automatic. When two or more devices come closer within the range of 30 feet to each other, they automatically start communicating. Blue tooth has a standardized protocol. Blue tooth uses the technology called frequency hopping and avoids interference with other wireless devices.

The energy consumption of blue tooth will not drain the battery. Data and voice communication can be shared using blue tooth, which is of great use for mobile phones and headsets. Upto seven blue tooth devices can be connected to each other within a range of 30 feet. Blue tooth has practically enormous applications.

There are a few disadvantages too with a blue tooth. Blue tooth offers data transfer rate in the range of 1 MB ps while the data transfer rate is comparatively faster for infrared which has a rate of 4 MB ps. Security is a drawback of blue tooth while infrared has inherent security due to its line of sight. Blue tooth is prone to interception and attack due to its great range and radio frequency.

The advantages of blue tooth surpass the disadvantages and therefore blue tooth is still by far the best for short-range wireless technology.