What is discrimination on a metal detector? How does does it work?

Question:

What is discrimination on a metal detector? How does does it work?

Answer: 

It is the ability of a metal detector to eliminate or “ignore” specific types of metal. For example you may want your detector to ignore all iron targets in an area full of junk. Or you may want to have your detector set to only find silver to go after valuable old SA coins. Thus your detector can ignore junk items like bottle caps and also tell you what type of metal is under the coil.