The transmission magnetooptic (MO) azimuth rotation and ellipticity experiments are mostly performed at the normal incidence of a sensing beam. At the normal light incidence, the distinction between the perpendicular and parallel polarizations with respect to the plane of incidence disappears. In isotropic media, the ellipsometric methods can provide useful information at oblique incidence only, and the normal incidence is employed in the polarization independent reflectance and transmittance spectroscopy. The inconvenient beam-splitting is removed in MO spectroscopic and MO magnetometric setups using the configurations with small angles of incidence. In the absence of any in-plane optical anisotropy, the response includes the Faraday effect and normal incidence MO polar Kerr effect as special cases. An easy saturation with the polar magnetization during the writing process and the stability of the particular magnetization polarity is required for the applications in the MO recording technology.