What does a box plot illustrate?

A box plot, often referred to as a whisker plot, provides a visual summary of key statistics of a dataset, particularly focusing on the central tendency and dispersion. The box itself represents the interquartile range (IQR), encapsulating the middle 50% of the data, while the horizontal line within the box marks the median. The “whiskers” extending from the box illustrate the range of the data, capturing the minimum and maximum values within a defined limit, typically excluding outliers.

This visualization is especially useful in identifying the spread and skewness of data while succinctly conveying how the various data points are distributed. It highlights the median, which is central to the dataset, and the quartiles, which allow for an understanding of the data's variability and distribution without providing specific data points.

The other options fail to capture this broader purpose: one option suggests a lack of details, while another focuses narrowly on individual frequencies, missing the overall summary that box plots provide. A final choice emphasizes only the extremes of the dataset, neglecting the critical insights offered by the quartiles and median represented in a box plot.