Find out more about seven of the most common graphs in statistics, including pie charts, bar graphs, and histograms. Find out more about seven of the most common graphs in statistics, including pie charts, bar graphs, and histograms. Menu. A Pareto diagram or bar graph is a way to visually represent qualitative data. Data is displayed If you are not sure about when to insert a bar chart for your work, you should think about the specific kind of your original data and your personal preference. Normally, compared to other types of charts, bar charts are better for showing and comparing very large sets of data or numbers. Types of Charts - Pie Charts It is crucial to choose the correct graph type based on the kind of data to be presented. If the independent and dependent variables are numeric, use line diagrams or scattergrams; if only the dependent variable is numeric, use bar graphs; for proportions, use bar graphs or pie charts. These are briefly described below.