What are 3D plots? When are they useful?

3D plots are created using X, Y and Z data points. They are useful at looking at relationships between 3 variables. It is always possible to represent more than two variables in a 2-D graphic. However, it will be more visual to add a third dimension. Simple bar plots or scatter plots become more informative when adding a third dimension. The addition of another dimension to a plot also enables you to access new types of plot such as surface plots. In fact, interactive rotating 3D plots can sometimes reveal aspects of the data not otherwise apparent.