It is a graphical representation of the Pareto Set and known as Pareto Front or Pareto Frontier. Given an optimization problem with two objective functions, it is an easy way to asses the solution obtained. For optimization problems with more than two objective functions, the user can choose the obective function to plot in each axis and replot as desired.
Clicking over the graph opens a bigger graph for easier visualization.
Additionally, a baseline design can be added to the Pareto Front Graph by clicking in the Baseline button. A window as shown in figure 9 appears where you can enter the information. Check the box and refresh the plots to view the baseline design plotted.