Donut Charts (also known as Doughnut) are quite alike the Pie Charts; they’re being used for the same purposes and function the same, restrictions are the same: they cannot have more than one series, it’s better to use no more than 7 categories in a Donut, there should be no negative values and as less as possible next-to-zero values. The main and only difference between Pie and Doughnut Charts is a hole in the middle. This inner area can be used to put labels there or some other text.
There is percentage of the ACME Corp. sales from 5 different retail channels described in this chart. Labels are enabled, but some of them cannot be seen because some of slices are too narrow for a label to fit it. Click and hover the legend items or the donut slices to make them exploded/not exploded or highlight them.