Bar and column charts are one of the most frequently used chart types. They are simple to understand, simple to make, and their visual structure matches the structure of a lot of data. They also have two variations that can be really useful for slightly more complex data structures. Grouped and stacked column charts are great ways to indicate other relationships in the structure of data, but there are subtle differences between what each one communicates, and using the right chart can make a big difference.
Both grouped and stacked column charts show a grouped structure in the data they represent, and they both can show a hierarchy one level deep. The differences are what makes them powerful, though.
Grouped bar charts are good for comparing between each element in the categories, and comparing elements across categories.
The grouping makes it harder to tell the difference between the total of each... keep reading