A IQR means the interquartile range, it would divide the data into 4 different parts called quartiles. Quart means 4!
The quartiles are called quartile 1, quartile 2, quartile 3, and quartile 4 or easier Q1, Q2, Q3, and Q4
It is used to tell when other values are far from the central value called outliers, because they lie outside the range we want them to be. Like if the centers are 3 and there is a number 9, the outliers would be 9 because it is far from 3.
