Several effects accompanying the propagation of electromagnetic waves through magneto-ordered media are discussed. First the information writing obtained by cooling through the Néel point of the antiferromagnetic substrate coupled by exchange interaction with the magnetic film is considered. By changing the exchange coupling it is possible to write and steadily retain arbitrary microdomain configurations. Peculiarities of magnetooptic effects were predicted by us and discovered in magnetically gyrotropic media with preset space distribution of magnetization. At the end, data on the photomagnetic effect in film of Mg-Mn ferrite are discussed.