The program is based on the Adams-Skopek algorithm for mutational spectra comparison. This algorithm is currently viewed as the best for mutational spectra (Piegorsch and Bailer, Genetics, 136, 403-416, 1994).
The input for the program is an ASCII file containing two columns of integers. The output of the program is a p value; a p value of less than 0.05 indicates that the two spectra are unlikely to have arise by chance alone. If you wish, you can download the software.