The difference between the third and first quartiles in a dataset , representing the middle half of the data is Interquartile Range.
The interquartile range (IQR) is a measure of statistical dispersion, which is the spread of the data. It is defined as the difference between the 75th percentile (Q3) and the 25th percentile (Q1) of the data. In other words, the IQR is the range of the middle 50% of the data.
The IQR is a robust measure of dispersion, which means that it is not as sensitive to outliers as other measures of dispersion, such as the range or the standard deviation. This is because the IQR only considers the middle 50% of the data, so it is not affected by extreme values at either end of the distribution..