Box plots, also known as box-and-whisker plots, provide a concise visual summary of a distribution's key statistical properties. The rectangular box spans from the first quartile (25th percentile) to the third quartile (75th percentile), capturing the middle 50% of the data. For more information, see Using Histograms to Understand Your Data. It plays an important role. Distribution box The system diagram usually shows the electrical connection and configuration inside the distribution box in a graphical way, including busbars, circuit breakers, fuses, load devices and other elements.