Discussion on the Terminology for Nondestructive Testing——Magnetic Field

The wrong description on the expression of magnetic field in the related literature was pointed out. The magnetic field is the material, not the space. It is suggested that the definition of the term of magnetic field is best expressed as: a field, existing by the presence on the moving charge(or current, or pole) around and capable of transferring motion charge(or current, or pole) interaction force between the material, is terminated as the magnetic field.