Magnetic resonance is a method of countouring which is being used in diagnostics, most frequnetly in disclosing pathological processes inside tissues. It is being used in reserach purposes in order to study the structure of the observed sample. It acts in such a way that the observed sample is set in the external magentic field, interaction occurs between external magnetic field and protons, and longitudinal magnetization occurs. The observed sample is acted upon by a radio frequency pulse, which causes the resultant magnetization vector to rotate in a plane perpendicular to the direction of action of the external magnetic field, and as a consequence transverse magnetization occurs. When the RF pulse stops, the system relaxes, which means that it returns to its equilibrium state. There are two types of relaxation, longitudinal relaxation, 𝑇1 , and transverse relaxation, 𝑇2. Relaxation times are important parameters that affect the MRI imaging and the quality of the image obtained. In order to carry out imaging, it is necessary to convert the transmitted signal from the time domain to the frequency domain by Fourier transformation. Magnetic resonance imaging is also used in molecular spectroscopy. The resulting spectrum is used to determine the molecular structure.