A Stacked Area Chart helps to compare different variables by their quantities over a time interval. Every variable is stacked one upon the other with different colors or shading. The plotting of the shaded region is just, as the simple area graph, the difference is just that it has more variables, stacked over each other.
Why do you need it?
Using a stacked chart, we can compare many variables with the same interval axis by their quantities insight. This visualization is easy to summarize, effective to understand, and saves time. It looks attractive and pleasant to show in a presentation.
What kind of data you can visualize with it?
Assume you have a dataset with the same intervals, like months and numeric values associated with different variables every month. Then this chart could be beneficial to visualize. This will give a brief overview of which variable is in progress as compared to others in the same interval. We can analyze the trend or pattern of the dataset by this graph.