The Kolmogorov-Smirnov one sample test compares the cumulative distribution function of a sample to a theoretical distribution such as the normal, uniform, Poisson, or exponential distributions. It determines if two distributions differ or if an underlying probability distribution differs from a hypothesized distribution. To perform the test, the relative empirical frequency distribution is determined based on the sample and compared to the theoretical distribution by finding the midpoint and standard deviation of the sample.