Аннотация:Typical experimental dependences of the giant magnetoresistance of a spin tunnel element are compared to theoretical curves obtained using the classical Stoner–Wohlfarth theory of coherent magnetization reversal and a case of incoherent magnetization reversal with the formation of magnetic domains. It is established that the reversal of magnetization through the formation of a domain structure explains the difference between the experimental hysteretic curve and the Stoner–Wohlfarth theory.