Ferromagnetic material properties

The article Ferromagnetic material properties is intended to contain a glossary of terms used to describe (mainly quantitatively) ferromagnetic materials, and magnetic cores.
Formulae.
To describe a soft ferromagnetic material for technical use, the following parameters are specified:
Magnetic core parameters.
These parameters used e.g. in Philips' handbook and Magnetic Materials Producers Association "Soft Ferrites, A Users Guide".