Hall Effect:The Hall effect is the production of a voltage difference (the Hall voltage) across an electrical conductor transverse to an electric current in the conductor and a magnetic field perpendicular to the current.
Anisotropic Magnetoresistance (AMR): Anisotropic magnetoresistance is a type of magnetoresistance where the electrical resistance of a material depends on the angle between the direction of the current and the direction of the magnetization.
Giant Magnetoresistance (GMR): Giant magnetoresistance is a quantum mechanical effect observed in thin film structures, consisting of alternating ferromagnetic and non-magnetic layers, where the electrical resistance of the material depends on the relative orientation of the magnetizations in the adjacent ferromagnetic layers.