In the stories of plucked string instruments often the words of the mediator and the mediator. So all you need to know what it is.
The mediator is a thin Deposit of plastic, metal, or bone. Her touch the strings while playing the mandolin, domra, and other similar tools.
Sometimes the mediator is in the form of an open ring with the "claw" and is worn on the finger. Such a mediator is called a plectrum.