Histogram

http://www.fsec.ucf.edu/en/research/buildings/schools/images/histogram.gif

Histograms provide a method of visualizing frequency data in intervals. They can be used for discrete or continuous data. This histogram gives the energy use for fractions of the sample, and is categorizing it into annual energy use per square foot. It is based on a 1996 survey of Florida public schools. The two largest bars (in histograms area of the bars is the key as opposed to height) occur just before and just after 50 btu/sqft and occurred in between .175 and .2 of the sample.

http://www.statcan.gc.ca/edu/power-pouvoir/ch9/histo/5214822-eng.htm

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