I see those things all the time,but what are they? Is it a phone that you wear on your ear? I tried searching Wikipedia,and googeld ....but nothing just explains what they are and just gives a basic explanation.
Here is a short explanation based on personal experience: bluetooth is a wireless headset that connects to your mobile phone and lets you talk without having to fuss with cords around you, be aware that using bluetooth on your phone, makes the battery drain quicker.
to my understanding, its a thing u hook up 2 your phone, and u put it in your ear, and then when your phone rings, u can answer it by pressing a button on the ear-headset. But your phone has to b bluetooth capible. Bluetooth is also a way of sharing ringtones 4 free. I hope i didnt confuse u. I would ask a person who sold the stuff. Hope i helped.