Fast Pair
Fast Pair is a functionality, introduced by Google in October of 2017, which allows the easy pairing of bluetooth peripheral, such as a headphone, with an Android device. The Androide device needs to have at least Android 6000!6.0 
"Marshmallow" installed, additionally, the peripheral needs to explicitly support Fast Pair.[1]
The peripheral is therefore set into pairing mode, during which it emits special fast pair messages using Bluetooth Low Energy (Bluetooth LE). If an Android device receives such fast pair messages it will automatically start the pairing process. During that, the device sends a request to a server hosted by Google to get a description text and an image of the peripheral. Afterwards, a message is created and displayed in the notification are of the device. If the user taps on that message, the android device automatically sets up the connection with the bluetooth peripheral.[2]