Measures of spread are statistical tools that describe how data points in a dataset vary or disperse from the average. Common measures include range, which is the difference between the highest and lowest values, and standard deviation, which indicates how much individual data points deviate from the mean. These measures help to understand the distribution and variability of data. Another important measure is the interquartile range (IQR), which represents the middle 50% of the data by subtracting the first quartile from the third quartile. This helps to identify outliers and gives a clearer picture of data spread, especially in skewed distributions.