3. Advantages of Bluetooth

One advantage with Bluetooth working within a short range is that it only needs a tiny amount of radio power to work, less than a thousandth' of a Watt. ( A torch light uses about 1 Watt to light the bulb) so you can see this is a tiny amount of power. This means it is ideal for battery operated devices such as mobile phones.

Another advantage of Bluetooth is that it is completely automatic - every Bluetooth enabled device will sense the presence of another device within range. They can do this because they share a 'network protocol' that allows them to share data.

Another clever thing about the protocol is that it can reduce interference from other Bluetooth devices that are also exchanging data nearby. For example if Sam's mobile is exchanging data with Tom's mobile this will not interfere with Sarah's mobile also exchanging data with Mary's mobile nearby.