In descriptive statistics, summary statistics are used to summarize a set of observations, in order to communicate the largest amount of information as simply as possible. Statisticians commonly try to describe the observations in
a measure of location, or central tendency, such as the arithmetic mean
a measure of statistical dispersion like the standard deviation
a measure of the shape of the distribution like skewness or kurtosis
if more than one variable is measured, a measure of statistical dependence such as a correlation coefficient