What is a histogram?

a diagram consisting of rectangles whose area is proportional to the frequency of a variable and whose width is equal to the class interval.

explanation: A histogram is a chart that shows frequencies for. intervals of values of a metric variable. Such intervals as known as "bins" and they all have the same widths. The example above uses $25 as its bin width. So it shows how many people make between $800 and $825, $825 and $850 and so on.