Bluetooth Low Energy (BLE or ״Bluetooth Smart״), is a light-weight subset of classic Bluetooth, mainly used for applications in the IoT, healthcare, fitness, beacons, security, and home entertainment industries.
Bluetooth Smart provides considerably reduced power consumption and cost while maintaining a similar communication range.
Bluetooth Smart is not backward compatible with the previous Bluetooth protocol. The Bluetooth 4.0 specification permits devices to implement either or both of the LE and Classic systems.
Bluetooth Smart uses the same 2.4 GHz radio frequencies as Classic Bluetooth, which allows dual-mode devices to share a single radio antenna.