Bluetooth technology is a short-range communication (it can reach several tens of meters), which allows two devices to liaise and exchange any type of data. This technology uses radio waves on the frequency from 2.4 GHz to 2.485 GHz.
Once you activate the Bluetooth, the device will be able to detect others who are in the same frequency range and supports this type of technology. Once connected, the two devices can exchange files and other information to the maximum speed.
Bluetooth 4.0, also called Bluetooth Low Energy, introduces an important concept of reduced energy consumption, while maintaining a connection between devices, without a continuous transmission of data between them.
Mode Low Energy operates on the frequency of 2.4 GHz and uses a transceiver "Adaptive Frequency Hopping", to have a greater resistance to electromagnetic interference.
To optimize the data transfer, data packets are used smaller than previous versions of Bluetooth, at a speed of 1 Mbps, which leaned against the Wi-Fi protocol, you can reach up to 24 Mbps.
These measures have promoted a better signal coverage, which can be up to 60/100 meters, thus improving security by using an encryption algorithm AES 128-bit.