The first that you should know about Histograms (especially as a PMP aspirant) is not to call it a “Bar Chart”. In the World of PMP, Gantt Chart is also known as Bar Chart. Although you may find certain texts where Histogram is referred to as a “Vertical Bar Chart”.
But for our understanding in simpler terms, Histogram is basically a bar chart. It represents data by breaking it down into different categories and helping you make informed decisions.
The Histogram example above represents the number of open defects after the final round of Testing. As you can most probably guess, we have got more work to do before this code can go live. But since Histogram has helped segregating the defects by impact you know which defects are catastrophic and critical and thus require your immediate attention.
And yes, Histogram does look like a Pareto Chart without the trend line.
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