A histogram is a specialized version of a column chart that groups data into ranges. The invention of the histogram has been credited to Karl Pearson, who founded the world’s first university statistics department at University College London 1911.
The complicated, dictionary definition of a histogram is that it’s a “visual representation of frequency distribution using bars whose widths represent intervals and whose areas are proportional to the corresponding frequencies.” But all that really means is that a histogram is a special version of a column chart, which is itself just a vertical version of a bar chart.
Because histograms deal with a range of quantities, they’re useful for displaying large sets of data and showing where the data peaks, as well as the statistical significance of those peaks.
One of the most important things to be careful of with histograms is the bin width and bin offset. Since each bar represents a range of values, it is important to be aware that outliers may skew the value for some of the bars.
Histograms are the most commonly used charts for showing frequency distributions, which show how often a different value occurs in a set of data.
Use a histogram when you want to see the shape of a data’s distribution, especially if you want to see where data is most normally distributed.