What's the meaning of "Front" in "Pareto-Optimal Front"? I'm reading a paper about Multi-Objective Optimization Problem. I understand Optimal in Pareto sense, and I even know what is Pareto-Optimal Front somehow. But I can't find a relationship between the word Front and the concept. So, what's the meaning of this word in this context?
I think it is sort of short for "frontier" (as in boundary between one thing and another.)  The two canonical examples would be a weather front (the boundary between a cold airmass and a warm airmass) and a military front (the boundary between the areas controlled by a pair of belligerent armies).