[header] How to read histograms [title] Recognize the difference between a bar chart and a histogram. [step] Bar charts and histograms are similar, but with some very specific differences. A bar chart groups numbers into categories, while histograms group numbers into ranges. 
Histograms are generally used to show the results of a continuous data set such as height, weight, time, etc. [substeps] A bar graph has spaces between the bars, while a histogram does not.