Keith M. Bower explains the meaning of mean and standard deviation. This educational video gives insight in the basics of statistics. The relations between population mean and sample mean and between population standard deviation and sample standard deviation are explained. The mean gives an idea on the central tendency. Standard deviation gives an idea about how spread out the data are. Keith also explains how these two parameters, the joint sufficient statistics, define a normal distribution. He then learns us a last rule of thumb, when you look at a range of one standard deviation both ways from the mean 68 percent of the population will be in it.