This document defines skewness and kurtosis, which are measures of the shape of a probability distribution. Skewness measures asymmetry and can be positive, negative, or zero, indicating whether the distribution is skewed right, left, or symmetric. Kurtosis measures peakedness and how frequent extreme values are, with more peaked distributions having more frequent medium/large changes and less frequent very large changes. Graphs are mentioned as a way to visualize these properties of a probability distribution's shape.