Image source: http://standards.nctm.org/document/chapter7/data.htm
Box and Whisker Plots are used in reports to describe the distribution of a
data set according to percentiles. It helps people understand the range of values
for the first 25% of data, the second 25% of data, the third 25% of data, and
the fourth 25% of data. For example, the box and whisker plot above suggests
that beef franks typically have more calories than poultry (chicken) franks.