Short description of Classifion 1.5: Classifion is chemometrics software for classification of substances using their mass-spectra. The used discriminant analysis is based on Principal Component Analysis with Mahalanobis Distance (PCA-MD) - part of multivariate analysis. Classifion has been tested using mass-spectra, but there is no limitation to be used with any other kind of characteristic spectra (e.g. VIS, IR, NMR).