Do stars differ in spectra?

Spectral classes – classification of stars by their emission spectrum, primarily by the temperature of the photosphere. The differences in the spectra of stars are due to the difference in the physical properties of their atmospheres, mainly in temperature and pressure (which determine the degree of ionization of atoms). The type of spectrum also depends on the presence of magnetic and interatomic electric fields, differences in chemical composition, rotation of stars, and other factors.