A metal detector is an electronic induction device that allows to detect metal objects in a neutral or weakly conducting medium (in the soil, water, walls, wood, under the clothes and in the trunk, food products humans and animals, etc.), not contacting them, informing the fact of the operator, such as a sound signal, deflection, etc.).
I.e. in the term "detector" is built only the detection of the subject made of metal.
Metal detector is a device for determining not only the existence metal objects, but also able to classify, what material made the subject: from ferromagnetic or non-magnetic, i.e. discrimination.
Separation of metals according to their qualities, and is the basis of discrimination, i.e. the definition of "colored" or "black" metal, respectively.
Author: S. L. Dubrovsky