A nested pie-chart is often referred to as a donut chart. As the name explains a nested pie-chart is a multi-level pie chart that allows the analyzer to display multiple series in a single visualization plotted altogether side-by-side. Every pie takes values corresponding to counts in a group, and it is compared with data of a category across different groups. And for better understanding, every category is colored distinctly. In the above visualization, we have two considerable factors like ‘the number of runs’ and ‘a number of experiments’. Each pie is either grouped by the number of experiments or the number of runs based on user specification. For instance, if we choose to group the chart with runs, we have a multi-level pie chart showcasing the values scored across the experiments 1 to 6. For every pie, we have a considerable factor named runs, and in total, we have fourteen pies with experiments ranging from 1 to 6. For instance, the values of run 1 in group 1 are the number of runs scored for experiments 1 to 6. And similarly, when we choose the experiment we have 6 groups in the chart representing the experiment and runs being the internal value for every group.