What is the relationship between spectral type and temperatureo a star?

The spectral type of a star is directly related to its temperature, as it categorizes stars based on their spectral characteristics, which are influenced by their surface temperatures. The classification system ranges from O-type stars, which are the hottest (over 30,000 K), to M-type stars, which are the coolest (below 3,500 K). As the temperature increases, the star emits more light at shorter wavelengths, leading to different absorption lines in their spectra. This relationship allows astronomers to infer a star's temperature based on its observed spectral type.