The aim of this paper is to introduce a new tool for a simple identification of spectral types. We use methods of statistical spectroscopy, in particular the method of intensity-distribution moments. The statistical approach revealed a characteristic behavior of moments of the stellar spectra for different spectral types. The transition from one spectral type to another may be expressed as a regular function of appropriate moments of the intensity distribution of the spectra. Moment-based diagrams localize particular spectral types in different areas of the plots. Since the intensity-distribution moments may be easily derived from the observed spectra, the presented method facilitates a simple auxiliary tool for the classification of stars to specific spectral types. It is also helpful in checking the correctness of the existing classifications. The intensity-distribution moments depend on all kinds of stellar characteristics, including the metallicity and the age. Therefore, using an inverse approach, from the knowledge of moments one may predict these properties.