Magnetic materials have been of importance to mankind for several thousand years. Lodestone is believed to have been instrumental in winning a decisive battle for the first emperor of China fought in a dense fog against the barbarians ca. 2600 bc. Many branches of science, and indeed our daily lives, depend on magnetic materials and magnetic characterization of one form or another, from high-density magnetic recording media and read-heads in computers to magnetic resonance imaging. Condensed matter physicists and materials researchers also rely heavily on magnetic characterization for the understanding and the exploration of new materials.