A box plot, or box-and-whisker plot, is a way of graphically depicting groups of numerical data through their quartiles. To make a box plot, the data is first arranged in numerical order and divided into quartiles. A box is drawn from the first quartile to the third quartile, with a line drawn inside the box at the second quartile (the median). Whiskers extend from the edges of the box to show the range of the rest of the data.