In statistics, variation refers to the measure of how spread out the data is around the center of the data. It is a way to show how data is dispersed or spread out. There are different measures of variation, and the most commonly used ones are range, interquartile range, standard deviation, and variance. These measures of variation are statistics of how far away the values in the observations (data points) are from each other. The range is the difference between the smallest and the largest value of the data. The interquartile range is the difference between the first and third quartiles (Q1 and Q3), and it is a measure of how data is spread around the mean. Standard deviation measures how far a typical observation is from the average of the data, and it is important for many statistical methods. Variance is the average of squared distances from the mean, and it tells you how far a data set is spread out. Variability is also referred to as spread, scatter, or dispersion.