The magneto-optic Kerr effect is similar to the Faraday effect, which describes changes to light transmission through a magnetic material. In contrast, the magneto-optic Kerr effect describes changes to light reflected from a magnetic surface.
Both the magneto-optic Kerr effect and the Faraday effect involve changes in light interaction with magnetic materials. However, while the Faraday effect focuses on transmission, the magneto-optic Kerr effect concentrates on reflection.