Which of the following is true regarding the standard deviation?

The standard deviation is a measure of variability or the spread of data points in a set of data. It is calculated by taking the square root of the variance, which is the average of the squared differences from the mean. It is expressed in the same unit of measurement as the data. In general, a lower standard deviation indicates that the data points tend to be closer to the mean and a higher standard deviation indicates that the data points are spread out more from the mean.