Some materials attract to a magnet while other materials have little or no interaction at all. The materials that attract to a magnet are said to have Ferromagnetic properties. Iron, Nickel and Cobalt are the most common ferromagnetic materials. They all have a level of Permeability that allow them to become attracted to an external magnetic field. They also have a level of magnetic Coercivity which under the influence of a strong external magnetic field, may cause the atoms to become magnetically aligned. When the external magnetic field is removed, the Remanence of the magnetised material may allow the material to stay indefinitely magnetised.

Magnetic fields impact Ferromagnetic material by aligning the crystalline structure in the molecules. The more Coercivifty a Ferromagnetic material has, the more aligned and more intense the alignment, and the stronger the magnetic field produced. A steel screwdriver tip can easily be magnetised by sliding a magnet against the tip in one direction. The molecular structure changes in the tip and allows it to pick up or hold metal screws. The induced magnetic field in Ferromagnetic material can be permanently damaged or greatly reduced under extreme or unfavourable conditions. Heating any Ferromagnetic material above a certain temperature or subjecting the material to consistent physical impact can cause the crystalline structures to become misaligned. The material may then lose its magnetic capabilities.