The experimental data on the structure of and the structural defects and structural relaxation in amorphous metallic alloys are reviewed. The elastic and inelastic properties of amorphous metallic alloys and the effect of disorder in the arrangement of atoms on the ferromagnetic properties of amorphous metallic alloys are also studied. Magnetoelastic phenomena are discussed in detail: the $\Delta E$ effect and magnetomechanical damping. Possible applications of amorphous metallic alloys in microelectronics, video recorders, and different types of transducers and sensors are discussed.